Laws of Motion
- State Newton’s Second Law of Motion.
- If action and reaction are always equal and opposite, why don’t they always cancel each other?
- Explain why a cricketer moves his hands backwards while catching ball?
- The leaves fall when a tree is shaken. Give reason.
- Why is it difficult to run fast on sand?
- If a moving bullet striking a block of wood on a frictionless table embeds inside it what happens to the KE of the bullet?
- Is friction a necessary evil? Explain.
- Why do we slip on a rainy day?
- Can a body be regarded in a state of rest as well as in motion at the same time? Give an example.
- Explain how Newton’s first law of motion follows from the second law.
- Why is the kinetic friction less than the limiting friction?
- Explain why a coin placed on a cardboard covering a glass falls into the glass when the cardboard is pulled suddenly to one side?
- When a large heavy truck collides with a passenger car, the occupants of the car are more likely to be hurt than the truck driver. Why?
- Why is it easy to pull a lawn roller than to push it?
Work and Energy
- In a siphon, water is lifted above its original level during its flow from one container to another, where does it get the needed potential energy from?
- What is meant by elastic and inelastic collision?
- Differentiate between conservation of kinetic energy and conservation of linear momentum.
- Distinguish between conservative and non-conservative force.
- How does K.E. of an object change if its momentum is doubled?
- “The earth moving round the sun in an orbit is acted upon by a force; hence the work must be done on the earth by this force.” Do you agree with this statement?
- When a bus takes a turn, passengers are thrown away from the centre of the curved path. Why?
- A solid tied at the end of a string is revolved in vertical. At what point the tension in the string will be the greatest?
- Explain why a cyclist bend while going along curved road?
- Why are roads banked on curved path?
- What will happen to the value of ‘g’ if the earth stops rotating?
- The weight of a body is less inside the earth than on the surface. Explain.
- Why an astronaut in a space capsule orbiting the earth experiences a feeling of weightlessness?
- How does ‘g’ at a point vary with distance from the centre of the earth? Where is the highest value of ‘g’? Explain.
- Explain why the moon has no atmosphere?
- What do you mean by geo-stationary satellite? Explain?
- If the sun somehow collapsed to form a black hole, what effect would this event have on the orbit of the earth?
- Is it possible for a solid body to have no matter at it centre of gravity?
- What is the difference between centre of gravity and centre of mass of a system?
- Why is a cow more stable than a man?
- What is meant by the moment of a couple?
- Can a body be in equilibrium if it is in motion? Explain.
- Why is a horse more stable than a man?
- A man carrying a bucket of water on his hand always leans to the opposite side. Explain.
- Why a wrench of longer arm is preferred in comparison to a wrench of short arm?
- Explain why a man carrying a load on his back leans forward?
- During pregnancy, woman often develop back pains from leaning backward while walking. Why do they have to walk this way?
- A fan with blades takes longer time to come to rest than without the blades. Why?
- If the earth is struck by meteorites, the earth will slow down slightly. Why?
- Suppose that only two external forces act on a rigid body and the two forces are equal in magnitude but opposite in direction. Under what conditions will the body rotate?
- What is the counterpart of the mass and force in rotational motion?
- Explain why spokes are fitted in the cycle wheel.
- A dancer girl is rotating over a turntable with her arms outstretched. If she lowers her arms how does this affect her motion?
- A rigid, lighter than air balloon filled with Helium cannot continue to rise indefinitely. Why?
- Why bridges are declared unsafe after a long use?
- Explain which one is more elastic- rubber or steel.
Periodic Motion (Simple Harmonic Motion)
- If a pendulum clock is taken to a mountain top, does it gain or lose time?
- On what factors does the time period of a simple pendulum depend?
- What are the drawbacks of simple pendulum?
- A pendulum clock is taken to moon. Will it gain or lose time?
- A body is moving in a circular path with constant speed. Is this motion a simple harmonic?
- Why does ice float in water?
- Why is the bottom of a ship made heavy?
- Steel balls sink in water but they don’t sink in mercury. Why?
- Does a ship sink more in river water or in sea water? Explain.
- State the laws of flotation.
- What are centre of buoyancy and metacentre?
- Why is easier to lift a body in a liquid than in air?
- A helium filled balloon rises to a certain height and then halts. Why?
- A cork is floating in water. What is the apparent weight of the cork?
- How will you make difference between density and specific gravity of a body?
- If a cork is released from the bottom of a jar filled with water, what will happen and why?
- How will you justify that stone is more rigid than iron?
Heat and Temperature
Quantity of Heat
Thermal Properties of Matter
Transfer of Heat
First Law of Thermodynamics
Second Law of Thermodynamics
Reflection at curved mirrors
Refraction at plane surfaces
Refraction through prisms
Capacitance and Dielectrics