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

A rocket is moving at a constant speed in space by burning its fuel and ejecting out the burnt gases through a nozzle. Answer the following

1) Is there any change in the momentum of the rocket? if yes, what causes the change in momentum?

2) Is there any force acting on the rocket? if yes, how much?

State Newton's third law of motion.

Name and define the S.I. and C.G.S. units of force. How are they related?

A body X of mass 5 kg is moving with velocity 20 m s^-2 while another body Y of mass 20 kg is moving with velocity 5 m S^-1. Compare the momentum of the two bodies.

Calculate the acceleration produced in a body of mass 50 g when acted upon by a force of 20 N.

A car of mass 600 kg is moving with a speed of 10 ms^-1 while a scooter of mass 80 kg us moving with a speed of 50 ms^-1. Compare their momentum.

A car of mass 600 kg is moving with a speed of 10 m^-1 while a scooter of mass 80 kg is moving with speed of 50 m s^-1. which vehicle will require more force to stop it in the (1) same interval of time (2) same distance

Is moment of force a scalar or a vector?

State two factor on which moment of force about a point depends.

Write the expression for calculating the moment of force about a given an axis.

State one way to reduce the moment of given force about a given axis of rotation.

What do you understand by the clockwise and anticlockwise moment of force? When is it taken positive?

The stone of hand flour grinder is provided with a handle near its rim. Give reason.

It is easier to turn the steering wheel of a large diameter than that of a small diameter. Given reason.

A spanner (or wrench) has a long handle. Why?

A, B and C are the three forces each of magnitude 4 N acting in the plane of the paper as shown in Figure. The point O lies in the same plane.

1. Which force has the least moment about O? Give a reason.
2. Which force has the greatest moment about O? Give a reason.
3. Name the forces producing
   (a) Clockwise
   (b) anticlockwise moments.
4. What is the resultant torque about the point O?

A body is acted upon by two forces of magnitude F but in opposite directions. State the effect of the force if both forces act at the same point of the body.

Give two examples of a couple's actions in our daily life.

The moment of a force about axis depends ______.

The moment of a force of 10 N about a fixed point O is 5 N m. Calculate the distance of the point O from the line of action of the force.