(English Medium) ICSE Class 9 - CISCE Question Bank Solutions

A ball is thrown up with a speed of 4.9 ms^-1.
Prove that the time of ascent is equal to the time of descent.

Where will you weigh more: at the centre of the earth or at the surface of the earth?

Where will you weigh more: at the moon's surface or at the earth's surface?

What is meant by the equation :
`g= Gxxm/r^2`
where the symbols have their usual meanings.

At what height above the earth's surface would the value of acceleration due to gravity be half of what it is on the surface? Take the radius of earth to be R.

A force can produce ________, In an object at rest. It can __________ an object and change its __________ of motion.

What does a force do in the following case?
You pull the skin of your arm

What does a force do in the following case?
You twist a piece of rubber.

What does a force do in the following case?
You apply brakes to a running car.

What does a force do in the following case?
You catch a kicked ball.

You can change the direction in which an object is moving by___________.

Name and state the action and reaction in the following case:
A book lying on a table.

Name and state the action and reaction in the following case:
A person walking on the ground.

Name and state the action and reaction in the following case:
Hammering a nail.

Why does a ball moving on a table top eventually stops?

Two equal and opposite forces acting at the same point on a stationary body. Will the body move? Give reason to explain your answer.

State the law of gravitation. Why is it called universal?

What is the difference between gravity and gravitation?

Gravity is another kind of ________. It exerts all through the ________. The Sun's gravity keeps the ___________ in their orbits. Gravity can only be felt with very large ________.

Explain why:
The atmosphere does not escape.