Naomba anitumie
Whatsapp: 0717505153
Email: immambise05@gmail.com]]><![CDATA[Physics Syllabus]]>
http://www.myelimu.com/thread-A-LEVEL-Physics-Syllabus
Sat, 05 Mar 2016 07:20:31 +0000http://www.myelimu.com/thread-A-LEVEL-Physics-Syllabus
Pakua syllabus ya physics advanced level
Jamani wadau Kuna yeyote mwenye notes Za phyisics a-level anitafute
Kwa mawasiliano haya
Sumu/whatsapp:0713879032
Email:zagaloemanuel610@gmail.com
physics a level syllabus.doc
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]]>
Pakua syllabus ya physics advanced level
Jamani wadau Kuna yeyote mwenye notes Za phyisics a-level anitafute
Kwa mawasiliano haya
Sumu/whatsapp:0713879032
Email:zagaloemanuel610@gmail.com
physics a level syllabus.doc
File Type:
Downloaded:
22 times
Size:
77.5 KB
]]><![CDATA[Basic And Applied Mathematics]]>
http://www.myelimu.com/thread-Basic-And-Applied-Mathematics
Sun, 12 Jul 2015 10:26:11 +0000http://www.myelimu.com/thread-Basic-And-Applied-Mathematics
]]>
]]><![CDATA[Various Questions For Form One]]>
http://www.myelimu.com/thread-O-LEVEL-Various-Questions-For-Form-One
Mon, 23 Mar 2015 07:57:30 +0000http://www.myelimu.com/thread-O-LEVEL-Various-Questions-For-Form-One
Multiple choice questions.
[list=lower-roman]
[*]When using measuring cylinder one precaution to be taken is
Check for zero error
Look at the meniscus from below the level of the water surface.
Position the eye in line with the base of the meniscus.
Obtain more readings by looking from more than one direction.
1. Choose and write the letter of the most correct answer.
(i) A physical quantity that cannot be derived from other physical quantities is known
as a
A. Scalar quantity C. Derived quantity
B. Small quantity D. Base quantity
(ii) A microsecond is equivalent to
1/1000 B. 1/10000 C. 1/1,000,000 D. 1/100,000
(iii) 1 milligram is equivalent to
1/1,00,000 B. 1/100,000 C. 1/10,000 D. 1/1000
(iv) Express the number 0.000000059 using Scientific notation.
5.9 x 10^{-8} B. 5.9x10^{-9} C. 5.9x10^{-7} D. 5.9x10^{-6}
(v) Which of the following physical quantity is not a derived quantity?
A. Temperature C. Speed
B. Acceleration D. Pressure
(vi) Which of the following measurement has the largest value?
1.0x10^{2} km C. 1.0x10^{8}cm
1.0x10^{7}mm D. 1.0x10^{10} um.
(vii) 0.36 litres of water is equivalent to
036 cm^{3} C. 360 m^{3}
360 cm^{3} D. 0.36 m^{3}
(viii) If 0.35 litres of water is mixed with 0.15 litre of mercury, then the density of
the mixture will be
14.6g/cm^{3} C. 7.3 g/cm^{3}
4.78 g/l D. 4.78 g/cm^{3}
(ix) An object has a relative density of 7.0. Its density in kg/m3 is
7 B. 700 C. 7000 D. 0.7
(x) The force which attracts bodies to the centre of the earth is
A. the centre of gravity C. the centripetal force
B. The equilibrium force D. the gravitational force
4. The water collected in a measuring cylinder during an experiment using a Eureka can is 30 cm^{3}. When the object the displaced this volume was dried and weighed, it mass was found to be 90g, Calculate.
Its density in g/cm3
Its density in kg/m3
Its relative density (R.D)
5. (a) Define Density and hence relative density
(b) A block of wood has a mass of 64g and a volume of 80cm3. Calculate.
[list=lower-roman]
[*]the density of wood.
(ii) the additional mass that must be placed on the block 20 that it is just submerged
(sink) in water.
[list=lower-roman]
[*]A person who deals with study and research in the field of physics is called.
Physician C. Physicist
Physikos D. Physiologist
[list=lower-roman]
[*]The following are common apparatus used to measure volume in laboratory except.
Measuring cylinder C. Burette
Beam balance D. Pipette
[list=lower-roman]
[*]Which one is not an instrument for measuring length.
A ruler C. A micrometer screw gauge
Vernier calipers D. A balance.
[list=lower-roman]
[*]The following are the most factors which enable the breakout of five
Oxygen, fuel and heat
Oxygen; carbon dioxide and fuel
Oxygen, water and heat
Oxygen, heat sand
[list=lower-roman]
[*]A vernier caliper is used to measure
Distance of a car C. Diameter of a wire
Mass of a car D. Length of a wire.
[list=lower-roman]
[*]Physic is _______________________
A quantitative science
An experimental science
The most basic Science
A theoretical Science
SHORT ANSWERS QUESTIONS
Mention three fundamental quantities with their SI mints used in mechanics.
3. Mention the laboratory rules used in physics laboratory.
State any three sources of fire that can occur in physics laboratory.
(a) What is physics?
(b) What is a physics laboratory?
(a) List six laboratory rules
(b) Name four items found in a First Aid kit.
What are the four (4) possible hazards in physics laboratory
]]>
Multiple choice questions.
[list=lower-roman]
[*]When using measuring cylinder one precaution to be taken is
Check for zero error
Look at the meniscus from below the level of the water surface.
Position the eye in line with the base of the meniscus.
Obtain more readings by looking from more than one direction.
1. Choose and write the letter of the most correct answer.
(i) A physical quantity that cannot be derived from other physical quantities is known
as a
A. Scalar quantity C. Derived quantity
B. Small quantity D. Base quantity
(ii) A microsecond is equivalent to
1/1000 B. 1/10000 C. 1/1,000,000 D. 1/100,000
(iii) 1 milligram is equivalent to
1/1,00,000 B. 1/100,000 C. 1/10,000 D. 1/1000
(iv) Express the number 0.000000059 using Scientific notation.
5.9 x 10^{-8} B. 5.9x10^{-9} C. 5.9x10^{-7} D. 5.9x10^{-6}
(v) Which of the following physical quantity is not a derived quantity?
A. Temperature C. Speed
B. Acceleration D. Pressure
(vi) Which of the following measurement has the largest value?
1.0x10^{2} km C. 1.0x10^{8}cm
1.0x10^{7}mm D. 1.0x10^{10} um.
(vii) 0.36 litres of water is equivalent to
036 cm^{3} C. 360 m^{3}
360 cm^{3} D. 0.36 m^{3}
(viii) If 0.35 litres of water is mixed with 0.15 litre of mercury, then the density of
the mixture will be
14.6g/cm^{3} C. 7.3 g/cm^{3}
4.78 g/l D. 4.78 g/cm^{3}
(ix) An object has a relative density of 7.0. Its density in kg/m3 is
7 B. 700 C. 7000 D. 0.7
(x) The force which attracts bodies to the centre of the earth is
A. the centre of gravity C. the centripetal force
B. The equilibrium force D. the gravitational force
4. The water collected in a measuring cylinder during an experiment using a Eureka can is 30 cm^{3}. When the object the displaced this volume was dried and weighed, it mass was found to be 90g, Calculate.
Its density in g/cm3
Its density in kg/m3
Its relative density (R.D)
5. (a) Define Density and hence relative density
(b) A block of wood has a mass of 64g and a volume of 80cm3. Calculate.
[list=lower-roman]
[*]the density of wood.
(ii) the additional mass that must be placed on the block 20 that it is just submerged
(sink) in water.
[list=lower-roman]
[*]A person who deals with study and research in the field of physics is called.
Physician C. Physicist
Physikos D. Physiologist
[list=lower-roman]
[*]The following are common apparatus used to measure volume in laboratory except.
Measuring cylinder C. Burette
Beam balance D. Pipette
[list=lower-roman]
[*]Which one is not an instrument for measuring length.
A ruler C. A micrometer screw gauge
Vernier calipers D. A balance.
[list=lower-roman]
[*]The following are the most factors which enable the breakout of five
Oxygen, fuel and heat
Oxygen; carbon dioxide and fuel
Oxygen, water and heat
Oxygen, heat sand
[list=lower-roman]
[*]A vernier caliper is used to measure
Distance of a car C. Diameter of a wire
Mass of a car D. Length of a wire.
[list=lower-roman]
[*]Physic is _______________________
A quantitative science
An experimental science
The most basic Science
A theoretical Science
SHORT ANSWERS QUESTIONS
Mention three fundamental quantities with their SI mints used in mechanics.
3. Mention the laboratory rules used in physics laboratory.
State any three sources of fire that can occur in physics laboratory.
(a) What is physics?
(b) What is a physics laboratory?
(a) List six laboratory rules
(b) Name four items found in a First Aid kit.
What are the four (4) possible hazards in physics laboratory
]]><![CDATA[Si Units]]>
http://www.myelimu.com/thread-Si-Units
Sat, 13 Sep 2014 11:29:58 +0000http://www.myelimu.com/thread-Si-Unitsof a second.The Kilogram is still defined in the 'old' way as the mass of a certain cylindrical piece of platinum iridium alloy kept at the International Office of Weights and Measures in Paris. It was originally defined as the mass ofof pure water at the temperature of maximum density, 4 degrees Celsius. An error at the time of this measurement meant the volume was actually Debate is taking place about a more fundamental definition.Time has taken the same unit, the second, for most of recorded history. It was defined in terms of physical constants in 1967, as the time interval occupied by 9192631770 cycles of a specified energy change in the Caesium atom.Together with the SI unit of temperature, Kelvin K, these units constitute the basis of the system of units in use today. Other units are defined in terms of these base units, and the system has the advantage of being self consistent so that no conversion factors are required when the same quantities appear in different equations.]]>of a second.The Kilogram is still defined in the 'old' way as the mass of a certain cylindrical piece of platinum iridium alloy kept at the International Office of Weights and Measures in Paris. It was originally defined as the mass ofof pure water at the temperature of maximum density, 4 degrees Celsius. An error at the time of this measurement meant the volume was actually Debate is taking place about a more fundamental definition.Time has taken the same unit, the second, for most of recorded history. It was defined in terms of physical constants in 1967, as the time interval occupied by 9192631770 cycles of a specified energy change in the Caesium atom.Together with the SI unit of temperature, Kelvin K, these units constitute the basis of the system of units in use today. Other units are defined in terms of these base units, and the system has the advantage of being self consistent so that no conversion factors are required when the same quantities appear in different equations.]]><![CDATA[Projectile Motion Question]]>
http://www.myelimu.com/thread-Projectile-Motion-Question
Tue, 17 Jun 2014 06:42:15 +0000http://www.myelimu.com/thread-Projectile-Motion-Question
(1)how long will the arrow remain in air before hitting the ground.
(2)where will the arrow land in relation to the position of the track?]]>
(1)how long will the arrow remain in air before hitting the ground.
(2)where will the arrow land in relation to the position of the track?]]><![CDATA[Question.]]>
http://www.myelimu.com/thread-Question
Mon, 26 May 2014 12:47:29 +0000http://www.myelimu.com/thread-Question<![CDATA[Motion]]>
http://www.myelimu.com/thread-Motion
Sun, 25 May 2014 14:36:43 +0000http://www.myelimu.com/thread-MotionVELOCITY AND ACCELERATION
When the body is moving it either moves at constant velocity or it accelarates, or it deccerates. In order to investigate motion of a body, it is neccessary to measure displacement and time of motion. In order to measure these quantities accurately a ticker timer may be used because it can measure small intervals of time accurately.
Definitions
Velocity is the rate of change of displacement (velocity = displacement/time)
Acceleration is the rate of change of velocity [acceleration is change in velocity/time; a = (v – u)/t]
Uniform velocity is the constant rate of change of displacement.
Uniform acceleration is the constant rate of change of velocity.
Acceleration due to gravity is the constant rate of change of velocity of a body falling freely under gravitational force only.The ticker timer works by making dots at regular time intervals (constant frequency) on a paper tape running through it.The rate at which the ticker timer makes the dots is the frequency(f), which is frequency of the a.c. voltage connected to it.Time between any two dots is equal to the reciprocal of frequency(T=1/f).Time on a ticker tape = number of spaces on the tape divided by frequency of the ticker timer. (t = n/f).From the ticker tape: Velocity = distance occupied by the spaces divided by the time t.
FRICTION COMPASATION
When a tolley is made to move on a runway,friction makes the trolley slow down. To compensate for friction on the runway the runway is inclined until the component of the weight of the trolley along the runway is just enough to overcome the frictional force so that the trolley moves down the runway at constant speed.
Job-related skills In forming the groups and carrying out the activities ensure that the following are deliberately achieved.
Personal attributes: - motivation and imagination.
Communication: - Knowing and applying general and specialized vocabulary in physics.
Team work: - ability to cooperate and share tasks with colleagues.
Problem solving: - goal focused, seek out relevant information, identify constraints, evaluate alternatives and make decisions/ choices.
Implementation and application: - the ability to carry out complex operations and follow instructions to achieve accurate results.
Application of numbers: - ability to work with and present numerical data, using appropriate intermediate calculations.
Information skills: - ability to present evidence to meet the needs of different audiences using graphs, reports and images.
Innovation: ability to find a way around a given problem or task, or to improve on the performance of a device.
Motion basic concepts
Speed is the distance travelled in a given time. For example if a car travels 300km in 5 hours then its:Average Speed = Distance moved/Time = 300/5 = 60 km per hour.
Velocity is calculated using the same formula, but when the velocity is stated you also have to give the direction of travel. (So Velocity = speed and direction)When the velocity of an object changes, by getting faster or slower, we say there is a change in its acceleration. If a car increases its velocity from 10 miles per hour to 60 miles per hour in 10 seconds then its:
Acceleration = Change in velocity/Time taken = 50/10 = 5 miles per hour per hour.
Cheetahs can reach a top speed of between 100 and 120 km/hour.At full speed, a cheetah can cover 7-8 meters every stride and it takes four strides every second.
Question: How many meters will a cheetah cover in a second? Is this its speed or its velocity?
Not only does the cheetah have a high top speed - it also has rapid acceleration. It can accelerate from zero to 80km per hour in 3 seconds.Although very fast, cheetahs are not as strong as other predators such as a lion or leopard. But additional muscle mass would add to the cheetahs weight and slow it down.
Animal trackers can tell from animal footprints how fast they are travelling and whether they are getting faster or slowing down. When they go faster (accelerate) their footprints get wider apart, and when they slow down (decelerate) their footprints get closer together.Question: When animals go uphill would you expect their footprints to get closer together or further apart? Why?
]]>VELOCITY AND ACCELERATION
When the body is moving it either moves at constant velocity or it accelarates, or it deccerates. In order to investigate motion of a body, it is neccessary to measure displacement and time of motion. In order to measure these quantities accurately a ticker timer may be used because it can measure small intervals of time accurately.
Definitions
Velocity is the rate of change of displacement (velocity = displacement/time)
Acceleration is the rate of change of velocity [acceleration is change in velocity/time; a = (v – u)/t]
Uniform velocity is the constant rate of change of displacement.
Uniform acceleration is the constant rate of change of velocity.
Acceleration due to gravity is the constant rate of change of velocity of a body falling freely under gravitational force only.The ticker timer works by making dots at regular time intervals (constant frequency) on a paper tape running through it.The rate at which the ticker timer makes the dots is the frequency(f), which is frequency of the a.c. voltage connected to it.Time between any two dots is equal to the reciprocal of frequency(T=1/f).Time on a ticker tape = number of spaces on the tape divided by frequency of the ticker timer. (t = n/f).From the ticker tape: Velocity = distance occupied by the spaces divided by the time t.
FRICTION COMPASATION
When a tolley is made to move on a runway,friction makes the trolley slow down. To compensate for friction on the runway the runway is inclined until the component of the weight of the trolley along the runway is just enough to overcome the frictional force so that the trolley moves down the runway at constant speed.
Job-related skills In forming the groups and carrying out the activities ensure that the following are deliberately achieved.
Personal attributes: - motivation and imagination.
Communication: - Knowing and applying general and specialized vocabulary in physics.
Team work: - ability to cooperate and share tasks with colleagues.
Problem solving: - goal focused, seek out relevant information, identify constraints, evaluate alternatives and make decisions/ choices.
Implementation and application: - the ability to carry out complex operations and follow instructions to achieve accurate results.
Application of numbers: - ability to work with and present numerical data, using appropriate intermediate calculations.
Information skills: - ability to present evidence to meet the needs of different audiences using graphs, reports and images.
Innovation: ability to find a way around a given problem or task, or to improve on the performance of a device.
Motion basic concepts
Speed is the distance travelled in a given time. For example if a car travels 300km in 5 hours then its:Average Speed = Distance moved/Time = 300/5 = 60 km per hour.
Velocity is calculated using the same formula, but when the velocity is stated you also have to give the direction of travel. (So Velocity = speed and direction)When the velocity of an object changes, by getting faster or slower, we say there is a change in its acceleration. If a car increases its velocity from 10 miles per hour to 60 miles per hour in 10 seconds then its:
Acceleration = Change in velocity/Time taken = 50/10 = 5 miles per hour per hour.
Cheetahs can reach a top speed of between 100 and 120 km/hour.At full speed, a cheetah can cover 7-8 meters every stride and it takes four strides every second.
Question: How many meters will a cheetah cover in a second? Is this its speed or its velocity?
Not only does the cheetah have a high top speed - it also has rapid acceleration. It can accelerate from zero to 80km per hour in 3 seconds.Although very fast, cheetahs are not as strong as other predators such as a lion or leopard. But additional muscle mass would add to the cheetahs weight and slow it down.
Animal trackers can tell from animal footprints how fast they are travelling and whether they are getting faster or slowing down. When they go faster (accelerate) their footprints get wider apart, and when they slow down (decelerate) their footprints get closer together.Question: When animals go uphill would you expect their footprints to get closer together or further apart? Why?
]]><![CDATA[O-level Physics Past Papers Free]]>
http://www.myelimu.com/thread-O-level-Physics-Past-Papers-Free
Thu, 15 May 2014 16:32:55 +0000http://www.myelimu.com/thread-O-level-Physics-Past-Papers-Free
Once you download the app, no need for internet to access the papers again. Read any time any where...all you need is your smartphone or tablet.
The App is found here (Play Store):https://play.google.com/store/apps/details?id=com.myexample.Physics_TZ
Happy Reading!
]]>
Once you download the app, no need for internet to access the papers again. Read any time any where...all you need is your smartphone or tablet.
The App is found here (Play Store):https://play.google.com/store/apps/details?id=com.myexample.Physics_TZ
Happy Reading!
]]><![CDATA[Introduction To Nutrition.]]>
http://www.myelimu.com/thread-Introduction-To-Nutrition
Mon, 05 May 2014 06:29:24 +0000http://www.myelimu.com/thread-Introduction-To-Nutrition
There are two types of nutrients.
1/ Micronutrients
2/ Macronutrients
1. Macronutrients.
There are nutrient that are needed in large amount. They include proteins, carbohydrates and lipids.
2. Micronutrients.
These are nutrients that ate required only in small amount. They include vitamins and minerals.
TYPES OF NUTRITION.
There are two types of nutrition.
1. Autotrophic nutrition
2. Heterotrophic nutrition]]>
There are two types of nutrients.
1/ Micronutrients
2/ Macronutrients
1. Macronutrients.
There are nutrient that are needed in large amount. They include proteins, carbohydrates and lipids.
2. Micronutrients.
These are nutrients that ate required only in small amount. They include vitamins and minerals.
TYPES OF NUTRITION.
There are two types of nutrition.
1. Autotrophic nutrition
2. Heterotrophic nutrition]]><![CDATA[Projectile Motion]]>
http://www.myelimu.com/thread-A-LEVEL-Projectile-Motion
Wed, 26 Mar 2014 10:53:50 +0000http://www.myelimu.com/thread-A-LEVEL-Projectile-Motion
"projectile motion is the combination of horizontal motion with constant velocity and vertical motion with uniform motion"
is the definition true? and how about the two concepts of uniform motion and constant velocity differ?
may you explain these two terminologies as they applied in the projectile motion?]]>
"projectile motion is the combination of horizontal motion with constant velocity and vertical motion with uniform motion"
is the definition true? and how about the two concepts of uniform motion and constant velocity differ?
may you explain these two terminologies as they applied in the projectile motion?]]><![CDATA[Physics Form One And Form Two Syllabus!]]>
http://www.myelimu.com/thread-Physics-Form-One-And-Form-Two-Syllabus
Sat, 15 Mar 2014 08:17:48 +0000http://www.myelimu.com/thread-Physics-Form-One-And-Form-Two-SyllabusFORM ONE SYLLABUS
1 - Introduction to Physics
Concepts of Physics
Applications of Physics in real Life
2 - Introduction to Laboratory practice
***introduction***
Laboratory rules and safety
Laboratory apparatus
Basic principle of Scientific investigation
3 - Measurements
Concept of measurements
Basic fundamental quantities
Derived quantities
Importance of measurement
4 - Force
Concept of Force
Types of Forces
Effects of Forces
5 - Archimede's principle and law of froatation
Concept of Upthrust
Sinking and Floating
6 - Structure and Properties of matter
Matter
Elasticity
Adhesion and Cohesion
Surface tension
Capillarity
Diffusion
Osmosis
7 - Pressure
Concept of Pressure
Pressure due to Solids
Pressure in Liquids
Atmospheric pressure
8 - Work, Energy and Power
Work
Energy
Power
9 - Light - Part I
Concept of Light
Propagation and Transimission of Light
Reflection of Light
FORM TWO SYLLABUS
1 - Static electricity
Concept of Static electricity
The gold leaf electroscope
Capacitors
Charge distribution on a Conductor
Lightining
2 - Current electricity part-I
Current electricity
Simple electric circuit
3 - Magnetism
Concept of magnetism
Magnetization and Demagnetization
Magnetic fields of a magnet
Earth's magnetic field
4 - Forces in Equilibrium
Effect of Turning forces
Center of gravity of a body
Types of equilibrium
Applications of equilibrium
5 - Simple machines
**Introduction**
Levers
Pulleys
Inclined plane
Screw and screw Jack
Wheel and axle
The hydraulic press
6 - Motion in straight line
**introduction**
Distance and Displacement
Speed and Velocity
Acceleration
Equations of uniformly accelerated motion
Motion under gravity
7 - Newtons laws of motion
Inertia
Newton's first law of motion
Newton's second law of motion and momentum
Conservation of linear momentum
Newton's third law of motin
8 - Temperature
Concept of temperature
Measurements of temperature
9 - Sustainable energy sources
**introduction**
Water energy
Solar energy
Wind energy
Sea wave energy
Geothermal energy
Energy cycle
]]>FORM ONE SYLLABUS
1 - Introduction to Physics
Concepts of Physics
Applications of Physics in real Life
2 - Introduction to Laboratory practice
***introduction***
Laboratory rules and safety
Laboratory apparatus
Basic principle of Scientific investigation
3 - Measurements
Concept of measurements
Basic fundamental quantities
Derived quantities
Importance of measurement
4 - Force
Concept of Force
Types of Forces
Effects of Forces
5 - Archimede's principle and law of froatation
Concept of Upthrust
Sinking and Floating
6 - Structure and Properties of matter
Matter
Elasticity
Adhesion and Cohesion
Surface tension
Capillarity
Diffusion
Osmosis
7 - Pressure
Concept of Pressure
Pressure due to Solids
Pressure in Liquids
Atmospheric pressure
8 - Work, Energy and Power
Work
Energy
Power
9 - Light - Part I
Concept of Light
Propagation and Transimission of Light
Reflection of Light
FORM TWO SYLLABUS
1 - Static electricity
Concept of Static electricity
The gold leaf electroscope
Capacitors
Charge distribution on a Conductor
Lightining
2 - Current electricity part-I
Current electricity
Simple electric circuit
3 - Magnetism
Concept of magnetism
Magnetization and Demagnetization
Magnetic fields of a magnet
Earth's magnetic field
4 - Forces in Equilibrium
Effect of Turning forces
Center of gravity of a body
Types of equilibrium
Applications of equilibrium
5 - Simple machines
**Introduction**
Levers
Pulleys
Inclined plane
Screw and screw Jack
Wheel and axle
The hydraulic press
6 - Motion in straight line
**introduction**
Distance and Displacement
Speed and Velocity
Acceleration
Equations of uniformly accelerated motion
Motion under gravity
7 - Newtons laws of motion
Inertia
Newton's first law of motion
Newton's second law of motion and momentum
Conservation of linear momentum
Newton's third law of motin
8 - Temperature
Concept of temperature
Measurements of temperature
9 - Sustainable energy sources
**introduction**
Water energy
Solar energy
Wind energy
Sea wave energy
Geothermal energy
Energy cycle
]]><![CDATA[Kinetic Theory Of Matter]]>
http://www.myelimu.com/thread-Kinetic-Theory-Of-Matter
Thu, 13 Mar 2014 12:01:54 +0000http://www.myelimu.com/thread-Kinetic-Theory-Of-Matter
Increasing the volume of the container lowers the pressure
Decreasing the volume of the container increases the pressure
Increasing the pressure of a gas sample decreases its volume
Decreasing the pressure of a gas sample increases its volume
Boyle's Law
States that for a fixed mass of gas at constant temperature, the pressure is inversely proportional to the volume
P_{1}V_{1} = P_{2}V_{2}
Explanation
When randomly moving gas molecules hit the wall of the container, they exert a force on the wall.
Since pressure is defined as force per unit area, a gas exerts pressure.
If the volume of the gas is halved by halving the volume of the container, the number of molecules per cm^{3} in the container will be doubled.
The number of collisions of molecules with the wall in one second will also be doubled. Thus the pressure is doubled
Example 1
An air bubble at the bottom of a lake 40m deep has a volume of 1.5cm^{3}. What is the volume of the air bubble when it rises to the surface of the lake?
(1 bar of pressure is approximately equivalent to the pressure exerted by 10m of water)
Solution
Pressure at surface = p1 = 1 bar = pressure exerted by 10m of water
Pressure at bottom = p2 = p1 + pressure exerted by 40m of water = 50m of water
Volume at surface = v1
Volume at bottom = v2 = 1.5cm^{3}
Boyle's Law:
P_{1}V_{1} = P_{2}V_{2}
10 x v1 = 50 x 1.5
v1 = 7.5cm^{3}MCQ Questions1. Brownian motion provides evidence that
a. smoke particles consist of molecules
b. smoke particles are lighter than air molecules
c. air molecules are in continuous random motion
d. air molecules attract smoke particles
2. At room temperature the particles in a solid are best described as
a. stationary and far apart
b. stationary and close together
c. vibrating and close together
d. moving randomly and far apart
3. Liquids have a definite volume because
a. the molecules are held in fixed positions
b. forces between the molecules do not allow them to leave the liquid
c. the molecules do not vibrate
d. the molecules are packed close together in a regular pattern
4. The volume of a certain gas in a piston is reduced to 2/3 of its original value. What happens to the pressure of the gas?
a. increases by 2/3
b. increases by 3/2
c. decreases by 2/3
d. decreases by 1/3
5. The pressure of a gas in a piston is 1.5 bar when the volume is 10cm^{3}. The volume is increased and the pressure falls to 1.2 bar. By how much was the volume increased?
a. 2.5cm^{3}
b. 12.5cm^{3}
c. 8.0cm^{3}
d. 1.8cm^{3}
6. In one minute, a diver breathes 1 litre of air at an atmospheric pressure of 100 kPa. To breathe in the same mass of air in one minute, how much air would he need to breathe when the total pressure on him under water is 300 kPa?
a. 1/3 litre
b. 1/2 litre
c. 1 litre
d. 2 litres
e. 3 litres
7. The air in a large paper bag is heated. The bag is then found to rise through the surrounding cold air. This is because
a. the air in the bag has become less dense
b. the mass of the paper bag has decreased
c. heat always rises
d. the mass of air in the bag has increased
e. the chemical compositions of the air in the bag has changed
8. The motion of the molecule of two gases causes them to mix. What is this motion called?
a. Brownian motion
b. conduction
c. diffusion
d. evaporation
e. radiation
9. A student observes the Brownian motion of smoke particles in air with a microscope. She sees moving points of light. These points of light come from
a. air particles only moving randomly
b. air particles only vibrating
c. smoke particles only moving randomly
d. smoke particles only vibrating
e. both smoke and air particles moving randomly
10. Some gas trapped in a cylinder is compressed at constant temperature by a piston. Which of the following will not change?
a. density
b. mass
c. molecular spacing
d. pressure
e. volume
11. A given mass of air occupies 12 m^{3} at normal atmospheric pressure. If the pressure is increased to 4 times the original value without changing the temperature, what volume will the air occupy?
a. 3 m^{3}
b. 6 m^{3}
c. 24 m^{3}
d. 48 m^{3}
e. 192 m^{3}
12. When the temperature of a gas rises at constant volume, its molecules
a. move closer together
b. move with greater average speed
c. collide with one anther less often
d. exert smaller forces on one another
e. expand
13. What is a property of both liquids and gases?a. they always fill their containersb. they are incompressiblec. they can flowd. they have molecules in fixed positions
14. Which of the following is the correct explanation for the expansion of a substance when it is heated?a. The particles of the substance increase in numberb. The particles of the substance vibrate fasterc. The particles of the substance push each other further awayd. The particles of the substance expand
15. In the Brownian motion experiment, the evidence of the movement of molecules is inferred by observinga. the air particles moving randomlyb. the molecules moving randomlyc. the smoke particles moving randomlyd. the air particles colliding with the smoke particles
]]>
Increasing the volume of the container lowers the pressure
Decreasing the volume of the container increases the pressure
Increasing the pressure of a gas sample decreases its volume
Decreasing the pressure of a gas sample increases its volume
Boyle's Law
States that for a fixed mass of gas at constant temperature, the pressure is inversely proportional to the volume
P_{1}V_{1} = P_{2}V_{2}
Explanation
When randomly moving gas molecules hit the wall of the container, they exert a force on the wall.
Since pressure is defined as force per unit area, a gas exerts pressure.
If the volume of the gas is halved by halving the volume of the container, the number of molecules per cm^{3} in the container will be doubled.
The number of collisions of molecules with the wall in one second will also be doubled. Thus the pressure is doubled
Example 1
An air bubble at the bottom of a lake 40m deep has a volume of 1.5cm^{3}. What is the volume of the air bubble when it rises to the surface of the lake?
(1 bar of pressure is approximately equivalent to the pressure exerted by 10m of water)
Solution
Pressure at surface = p1 = 1 bar = pressure exerted by 10m of water
Pressure at bottom = p2 = p1 + pressure exerted by 40m of water = 50m of water
Volume at surface = v1
Volume at bottom = v2 = 1.5cm^{3}
Boyle's Law:
P_{1}V_{1} = P_{2}V_{2}
10 x v1 = 50 x 1.5
v1 = 7.5cm^{3}MCQ Questions1. Brownian motion provides evidence that
a. smoke particles consist of molecules
b. smoke particles are lighter than air molecules
c. air molecules are in continuous random motion
d. air molecules attract smoke particles
2. At room temperature the particles in a solid are best described as
a. stationary and far apart
b. stationary and close together
c. vibrating and close together
d. moving randomly and far apart
3. Liquids have a definite volume because
a. the molecules are held in fixed positions
b. forces between the molecules do not allow them to leave the liquid
c. the molecules do not vibrate
d. the molecules are packed close together in a regular pattern
4. The volume of a certain gas in a piston is reduced to 2/3 of its original value. What happens to the pressure of the gas?
a. increases by 2/3
b. increases by 3/2
c. decreases by 2/3
d. decreases by 1/3
5. The pressure of a gas in a piston is 1.5 bar when the volume is 10cm^{3}. The volume is increased and the pressure falls to 1.2 bar. By how much was the volume increased?
a. 2.5cm^{3}
b. 12.5cm^{3}
c. 8.0cm^{3}
d. 1.8cm^{3}
6. In one minute, a diver breathes 1 litre of air at an atmospheric pressure of 100 kPa. To breathe in the same mass of air in one minute, how much air would he need to breathe when the total pressure on him under water is 300 kPa?
a. 1/3 litre
b. 1/2 litre
c. 1 litre
d. 2 litres
e. 3 litres
7. The air in a large paper bag is heated. The bag is then found to rise through the surrounding cold air. This is because
a. the air in the bag has become less dense
b. the mass of the paper bag has decreased
c. heat always rises
d. the mass of air in the bag has increased
e. the chemical compositions of the air in the bag has changed
8. The motion of the molecule of two gases causes them to mix. What is this motion called?
a. Brownian motion
b. conduction
c. diffusion
d. evaporation
e. radiation
9. A student observes the Brownian motion of smoke particles in air with a microscope. She sees moving points of light. These points of light come from
a. air particles only moving randomly
b. air particles only vibrating
c. smoke particles only moving randomly
d. smoke particles only vibrating
e. both smoke and air particles moving randomly
10. Some gas trapped in a cylinder is compressed at constant temperature by a piston. Which of the following will not change?
a. density
b. mass
c. molecular spacing
d. pressure
e. volume
11. A given mass of air occupies 12 m^{3} at normal atmospheric pressure. If the pressure is increased to 4 times the original value without changing the temperature, what volume will the air occupy?
a. 3 m^{3}
b. 6 m^{3}
c. 24 m^{3}
d. 48 m^{3}
e. 192 m^{3}
12. When the temperature of a gas rises at constant volume, its molecules
a. move closer together
b. move with greater average speed
c. collide with one anther less often
d. exert smaller forces on one another
e. expand
13. What is a property of both liquids and gases?a. they always fill their containersb. they are incompressiblec. they can flowd. they have molecules in fixed positions
14. Which of the following is the correct explanation for the expansion of a substance when it is heated?a. The particles of the substance increase in numberb. The particles of the substance vibrate fasterc. The particles of the substance push each other further awayd. The particles of the substance expand
15. In the Brownian motion experiment, the evidence of the movement of molecules is inferred by observinga. the air particles moving randomlyb. the molecules moving randomlyc. the smoke particles moving randomlyd. the air particles colliding with the smoke particles
]]><![CDATA[Jinsi ya Kuandika Formulas na Equations]]>
http://www.myelimu.com/thread-Jinsi-ya-Kuandika-Formulas-na-Equations--56
Fri, 28 Feb 2014 14:24:22 +0000http://www.myelimu.com/thread-Jinsi-ya-Kuandika-Formulas-na-Equations--56
Tumeweka system ambayo itawezesha wanafunzi kuandika equations za formulas kwenye posts kwa urahisi. Topic hii ni ya maelekezo ya jinsi utakavyoweza kuandika equations hizo.
1. Kufugua equation
Kwanza inabidi uanze kwa kuandika {math} then equation yako halafu ukimaliza unafunga kwa {/math}. Mfano:-
{math}x=2{/math}. Kumbuka haya mabano inabidi uyaweke na kuyafunga kila kila equation, na katika maelekezo yote yanayofuata tuna-assume umeshafungua mabano ya {math}.
Pia, unaweza kuweka fraction ndani ya fraction! Mfano:- \frac{\frac{1}{x}+\frac{1}{y}}{y-z} italeta
Unaweza kufanya majaribio hapo chini kwa kureply na kisha kujaribu equation mbali mbali.
3. Powers and indices
Unaweza kuandika power kwa kuweka kialama cha "^" na indice kwa kuweka kialama cha _ . Mfano:-
x^n italeta
x^{2n} italeta
Index italeta n_i
n_{ij}italeta
4. Root Unaweza kuandika root kwa kuanza na \sqrt [namba ya nje] [namba za ndani]. Mfano:-
\sqrt[3]{\frac {x^2}{4xy-2}} italeta
x=\frac{-b\pm\sqrt{b^2-4ac}}{2a} italeta .
5. Brackets
Kuweka brackets, kuna njia mbili: Unaweza kuandika brackets kama kawaida, au kwa kuandika \left na \right. Angalia hapa chini:-
(\frac{x^2}{y^3}) italeta
\left(\frac{x^2}{y^3}\right) italeta
Ukiangalia hapa juu unagundua tofauti ya kutumia /left na kutumia mabano () kama kawaida. /left na /right inaleta mabano ambayo size yake inakuwa automatic kutokana na kilicho ndani yake.
Matrices Njia rahisi ya kuandika matrix ni \begin{matrix} a&b\\c&d \end{matrix} ambayo italeta .
Izungushie \left( ... \right) kupata . Alternatively, unaweza ukatumia \begin{pmatrix} ... \end{pmatrix} ambayo itazungushia matrix yako automatically na mabano.
NB: Alama ya // inaruka kwenda kwenye mstari mwingine.
Namna ya kuweka mabano
Kitu kingine cha kuzingatia ni jinsi haya mabano yanavyowekwa. Kama unataka mabano ya kawaida makubwa basi baada ya \left inabidi uweke bano la kawaida, yaani mfano \left(5)\right. Ila kama unataka mabano yenye mshale, basi utaandika \left{5 \left}
Symbols
Kama una swali au haujaelewa sehemu, tafadhali usisite kuuliza. Enjoy being a mathematician
]]>
Tumeweka system ambayo itawezesha wanafunzi kuandika equations za formulas kwenye posts kwa urahisi. Topic hii ni ya maelekezo ya jinsi utakavyoweza kuandika equations hizo.
1. Kufugua equation
Kwanza inabidi uanze kwa kuandika {math} then equation yako halafu ukimaliza unafunga kwa {/math}. Mfano:-
{math}x=2{/math}. Kumbuka haya mabano inabidi uyaweke na kuyafunga kila kila equation, na katika maelekezo yote yanayofuata tuna-assume umeshafungua mabano ya {math}.
Pia, unaweza kuweka fraction ndani ya fraction! Mfano:- \frac{\frac{1}{x}+\frac{1}{y}}{y-z} italeta
Unaweza kufanya majaribio hapo chini kwa kureply na kisha kujaribu equation mbali mbali.
3. Powers and indices
Unaweza kuandika power kwa kuweka kialama cha "^" na indice kwa kuweka kialama cha _ . Mfano:-
x^n italeta
x^{2n} italeta
Index italeta n_i
n_{ij}italeta
4. Root Unaweza kuandika root kwa kuanza na \sqrt [namba ya nje] [namba za ndani]. Mfano:-
\sqrt[3]{\frac {x^2}{4xy-2}} italeta
x=\frac{-b\pm\sqrt{b^2-4ac}}{2a} italeta .
5. Brackets
Kuweka brackets, kuna njia mbili: Unaweza kuandika brackets kama kawaida, au kwa kuandika \left na \right. Angalia hapa chini:-
(\frac{x^2}{y^3}) italeta
\left(\frac{x^2}{y^3}\right) italeta
Ukiangalia hapa juu unagundua tofauti ya kutumia /left na kutumia mabano () kama kawaida. /left na /right inaleta mabano ambayo size yake inakuwa automatic kutokana na kilicho ndani yake.
Matrices Njia rahisi ya kuandika matrix ni \begin{matrix} a&b\\c&d \end{matrix} ambayo italeta .
Izungushie \left( ... \right) kupata . Alternatively, unaweza ukatumia \begin{pmatrix} ... \end{pmatrix} ambayo itazungushia matrix yako automatically na mabano.
NB: Alama ya // inaruka kwenda kwenye mstari mwingine.
Namna ya kuweka mabano
Kitu kingine cha kuzingatia ni jinsi haya mabano yanavyowekwa. Kama unataka mabano ya kawaida makubwa basi baada ya \left inabidi uweke bano la kawaida, yaani mfano \left(5)\right. Ila kama unataka mabano yenye mshale, basi utaandika \left{5 \left}
Symbols
Kama una swali au haujaelewa sehemu, tafadhali usisite kuuliza. Enjoy being a mathematician
]]><![CDATA[Work, Energy and The Principle for Conservation of Energy]]>
http://www.myelimu.com/thread-Work-Energy-and-The-Principle-for-Conservation-of-Energy
Wed, 26 Feb 2014 05:03:24 +0000http://www.myelimu.com/thread-Work-Energy-and-The-Principle-for-Conservation-of-EnergyWork
Work is the product of the force on a body and the distance it moves in the direction of the force
Work done = force x distance moved in the direction of the force
Work is done whenever energy is changed from one form into another.
SI unit is joule (J)
Work is a scalar quantity
Energy
energy is defined as the capacity to do work
SI unit is joule (J)
Energy is a scalar quantity
Kinetic energy is the energy a body possesses due to its movement
kinetic energy can be classified into
translational kinetic energy: possessed by bodies in translational motion (eg moving train) =1/2 mv2
rotational kinetic energy: possessed by bodies in rotational motion (eg rotating merry-go-round)
potential energy is the energy a body possesses due to its position or state
potential energy can be classified into:
gravitational potential energy: possessed by a body due to its position = mgh
elastic potential energy: possessed by a body due to its strained state of being stretched or compressed
Eg. A ball of mass 500g is moving at a velocity of 5m/s. What is the kinetic energy of the ball?
kinetic energy = 1/2 mv2 = 1/2 x 0.5 x 5 x 5 = 6.25 J
Eg. Billy has a mass of 40kg. He runs up a flight of 20 steps, each of height 0.25m. Calculate his gain in gravitational potential energy
gain in gravitational potential energy = mgh = 40 x 10 x (20 x 0.25) = 2000 J
Principle of Conservation of Energy
States that "energy can neither be created not destroyed but can be transformed from one form into another with no change in its total amount."
Eg. A ball of mass 3kg is dropped from a height of 5m.
i. calculate the gravitational potential energy of the ball before it is dropped
ii. calculate the speed of the ball on hitting the ground
iii. if the ball bounces to a height of 3m, with what speed does it leave the ground?
iv. explain why the ball does not reach its original height when it bounces up again
i. gravitational potential energy = mgh = 3 x 10 x 5 = 150J
ii. The kinetic energy of the ball on hitting the ground is equal to the ball's original gravitational potential energy so the kinetic energy of the ball on hitting the ground = 150J
If the ball hits the ground with speed v,
1/2 mv2 = 150
v2 = (150 - 2)/3 = 100
v = 10ms-1
iii. The kinetic energy of the ball on leaving the ground is equal to its gravitational potential energy on rising to its maximum height, that is 3m.
The gravitational potential energy of the ball 3m above the ground = 3 x 10 x 3 = 90 J
The kinetic energy of the ball leaving the ground = 90 J
If the ball leaves the ground with speed v,
1/2 mv2 = 90v2 = (90 x 2)/3
v = 7.746ms-1
iv. Because part of its kinetic energy is changed into other forms of energy like sound and heat when it hits the ground
Eg. A pendulum bob of mass 0.5kg is moved sideways until it has risen by a vertical height of 0.2m. Calculate the speed of the bob at its
i. highest point
ii. lowest point
i. at the highest point, the kinetic energy of the bob = 0
if the speed of the bob at its highest point is v,
1/2 mv2 = 0
1/2 x 0.5 x v = 0
v2 = 0
v = 0
ii. according to the principle of conservation of energy, the kinetic energy of at the lowest point is equal to the gravitational potential energy at the highest point.
If the speed of the bob at its lowest point is v,
1/2 mv2 = mgh
v2 = 2 x 10 x 0.2 = 4
v = 2 m/s
Power and efficiency
Power is defined as the rate of doing work
Power = work done/time taken
SI unit is watt (W)
Efficiency is the ratio of useful output energy to the total input energy or the ratio of useful power to the total input power.
Efficiency = (useful output energy / input energy) x 100%
Eg. A crane can lift a 200kg mass through a vertical height of 5m in 4s. Calculate
i. the power output of the motor driving the crane
ii. the efficiency of the motor if the power input is 5kW
i. power output = work done/time taken = (200 x 10 x 5)/4 = 2500W
ii. efficiency of motor = (power output/power input) x 100% = (2500/5000) x 100% = 50%Friction
The net force that slows down moving objects
Acts in the opposite direction of motion of objec
1. Static friction
related to objects which are not moving.
amount of force applied = amount of friction
2. Moving friction
applied force does not affect friction
it can be affected by surface or sudden change in mass
Advantages of friction
enables walking
brakes of vehicles
Disadvantages
reduce efficiency of machinery
energy wasted as heat
Methods to reduce friction
lubricants
ball bearings
-----> so that moving parts are made smoother
]]>Work
Work is the product of the force on a body and the distance it moves in the direction of the force
Work done = force x distance moved in the direction of the force
Work is done whenever energy is changed from one form into another.
SI unit is joule (J)
Work is a scalar quantity
Energy
energy is defined as the capacity to do work
SI unit is joule (J)
Energy is a scalar quantity
Kinetic energy is the energy a body possesses due to its movement
kinetic energy can be classified into
translational kinetic energy: possessed by bodies in translational motion (eg moving train) =1/2 mv2
rotational kinetic energy: possessed by bodies in rotational motion (eg rotating merry-go-round)
potential energy is the energy a body possesses due to its position or state
potential energy can be classified into:
gravitational potential energy: possessed by a body due to its position = mgh
elastic potential energy: possessed by a body due to its strained state of being stretched or compressed
Eg. A ball of mass 500g is moving at a velocity of 5m/s. What is the kinetic energy of the ball?
kinetic energy = 1/2 mv2 = 1/2 x 0.5 x 5 x 5 = 6.25 J
Eg. Billy has a mass of 40kg. He runs up a flight of 20 steps, each of height 0.25m. Calculate his gain in gravitational potential energy
gain in gravitational potential energy = mgh = 40 x 10 x (20 x 0.25) = 2000 J
Principle of Conservation of Energy
States that "energy can neither be created not destroyed but can be transformed from one form into another with no change in its total amount."
Eg. A ball of mass 3kg is dropped from a height of 5m.
i. calculate the gravitational potential energy of the ball before it is dropped
ii. calculate the speed of the ball on hitting the ground
iii. if the ball bounces to a height of 3m, with what speed does it leave the ground?
iv. explain why the ball does not reach its original height when it bounces up again
i. gravitational potential energy = mgh = 3 x 10 x 5 = 150J
ii. The kinetic energy of the ball on hitting the ground is equal to the ball's original gravitational potential energy so the kinetic energy of the ball on hitting the ground = 150J
If the ball hits the ground with speed v,
1/2 mv2 = 150
v2 = (150 - 2)/3 = 100
v = 10ms-1
iii. The kinetic energy of the ball on leaving the ground is equal to its gravitational potential energy on rising to its maximum height, that is 3m.
The gravitational potential energy of the ball 3m above the ground = 3 x 10 x 3 = 90 J
The kinetic energy of the ball leaving the ground = 90 J
If the ball leaves the ground with speed v,
1/2 mv2 = 90v2 = (90 x 2)/3
v = 7.746ms-1
iv. Because part of its kinetic energy is changed into other forms of energy like sound and heat when it hits the ground
Eg. A pendulum bob of mass 0.5kg is moved sideways until it has risen by a vertical height of 0.2m. Calculate the speed of the bob at its
i. highest point
ii. lowest point
i. at the highest point, the kinetic energy of the bob = 0
if the speed of the bob at its highest point is v,
1/2 mv2 = 0
1/2 x 0.5 x v = 0
v2 = 0
v = 0
ii. according to the principle of conservation of energy, the kinetic energy of at the lowest point is equal to the gravitational potential energy at the highest point.
If the speed of the bob at its lowest point is v,
1/2 mv2 = mgh
v2 = 2 x 10 x 0.2 = 4
v = 2 m/s
Power and efficiency
Power is defined as the rate of doing work
Power = work done/time taken
SI unit is watt (W)
Efficiency is the ratio of useful output energy to the total input energy or the ratio of useful power to the total input power.
Efficiency = (useful output energy / input energy) x 100%
Eg. A crane can lift a 200kg mass through a vertical height of 5m in 4s. Calculate
i. the power output of the motor driving the crane
ii. the efficiency of the motor if the power input is 5kW
i. power output = work done/time taken = (200 x 10 x 5)/4 = 2500W
ii. efficiency of motor = (power output/power input) x 100% = (2500/5000) x 100% = 50%Friction
The net force that slows down moving objects
Acts in the opposite direction of motion of objec
1. Static friction
related to objects which are not moving.
amount of force applied = amount of friction
2. Moving friction
applied force does not affect friction
it can be affected by surface or sudden change in mass