(English Medium) ICSE Class 10 - CISCE Question Bank Solutions

Two bodies have masses in the ratio 3 : 4 when a force is applied on the first body. it moves with an acceleration of 6 ms^-2 . How much acceleration will the same force produce in the other body? 

A cricket ball of mass 100 g strikes the hand of a player with a velocity of 20 ms^-1 and is brought to rest in 0.01 s calculate

1) the force applied by the hand of the player.

2) the acceleration of the ball

A lead bullet of mass 20g, travelling with a velocity of 350 ms^-1, comes to rest after penetrating 40 cm in a still target. Find:

1) the resistive force offered by the target and 

2) the retardation caused by it

A body of mass 50g is moving with the velocity of 10 ms^-1. It is brought to rest by a resistive force of 10 N Find.

1) the retardation and 

2) the distance that the body will travel after the resistive force is applied.

A uniform car of mass 500g travels with a uniform velocity of 25 ms^-1 for 5 s. The brakes are then applied and the car is uniformly retarded and comes to rest in further 10 s calculate 

1) the retardation

2) the distance which the car travels after the brakes are applied 

3) The force exerted by the brakes.

A truck of mass `5 xx 10^3` kg starting from rest travels a distance of 0.5 km in 10 s when a force is applied on its calculate:

1) the acceleration acquired by the truck and

2) the force applied

A force od 10 kgf is applied on a body of mass 100 g initially at rest for 0.1 s calculate:

a) the momentum acquired by the body

b) the distance travelled by the body in 0.1s. Take g = 10 N kg^-1

Why is it easier to open a door by applying the force at the free end of it?

The adjacent diagram shows a heavy roller, with its axle at O, which is to be raised on a pavement XY. If there is friction between the roller and pavement, show by an arrow on the diagram the point of application and the direction of force to be applied. If pivoted at O, now will it go up?

When is work said to be done by a force?

State four ways in which machines are useful to us.

Name a machine to multiply force ?

Name a machine to change the point of application of force ?

In which of the following cases, is work being done?
(i) A man pushing a wall.
(ii) a coolie standing with a load of 12 kgf on his head.
(iii) A boy climbing up a staircase.

Express joule in terms of erg.

1 J = ______ calorie.

Differentiate between energy and power.

A boy of mass 40 kg climbs up the stairs and reaches the roof at a height 8 m in 5 s. Calculate:

1. the force of gravity acting on the boy,
2. the work done by him against the force of gravity,
3. the power spent by boy. (Take g = 10 m s^-2)

It takes 20 s for a person A of mass 50 kg to climb up the stairs, while another person B does the same in 15 s. Compare the work done.

A weight lifter lifted a load of 200 kgf to a height of 2.5 m in 5 s. Calculate:

1. the work done, and
2. the power developed by him. Take g = 10 N kg^-1