Question

Suppose a ball is thrown vertically upwards from a position P above the ground. It rises

to the highest point Q and returns to the same point P. What is the net displacement

and distance travelled by the ball? 1

2. A body is moving with a velocity of 10 m/s. If the motion is uniform, what will be the

velocity after 10 s? 1

3. Plot a graph between force applied on a body and the acceleration produced in the

given mass, assuming that the magnitude of force is constantly changing. 1

4. Suppose gravity of earth suddenly becomes zero, then which direction will the moon

begin to move if no other celestial body affects it? 1

5. Is it possible that a body be in accelerated motion under a force acting on the body, yet

no work is being done by the force? Explain your answer giving a suitable example. 1

6. Express average velocity when the velocity of a body changes at a non-uniform rate and

a uniform rate. 2

7. Prove that if the earth attracts two bodies placed at same distance from the centre of

the earth with the same force, then their masses are equal. 2

8. A bullet fired against a glass window pane makes a hole in it, and the glass pane is not

cracked. But on the other hand, when a stone strikes the same glass pane, it gets

smashed. Why is it so? 2

9. What happens to the kinetic energy when :

(i) the mass of the body is doubled at constant velocity?

(ii)the velocity of the body is doubled at constant mass?

(iii)the mass of the body is doubled but the velocity is reduced to half? 3

10. A bullet of 10 g strikes a sand bag at a speed of 103 ms-1 and gets embedded after

travelling 5 cm. Calculate

(i) the resistive force exerted by the sand on the bullet.

(ii) the time taken by the bullet to come to rest. 3​

Answer 1

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