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

State two conditions when the work done by a force acting on a body is zero.

State the condition when the work done by the force is positive

State the condition when the work done by the force is negative.

A force F when acts on a body, displace it by a distance d in a direction at an angle θ with the direction of the force. Write down the expression for the work done by the force.

State two conditions for work to be done.

What is the S.I. unit of work? Define it.

Justify the statement. “Power can be expressed as the product of force and velocity.”

State the practical unit mainly used in mechanical engineering and write down its equivalent in watt.

What happens to the power if the time for doing work is reduced from t second to t/10 second?

State the S.I. and C.G.S. units of energy. How are they related?

Relate 1 KWh (kilowatt hour) with joule.

What is meant by equilibrium and state the conditions of equilibrium of a body?

What do you mean by dynamic and static equilibrium? Give one example of each.

What is a couple?

One end of a spring is kept fixed while the other end is stretched by a force as shown in the diagram.

(i) Copy the diagram and mark on it the direction of the restoring force.
(ii) Name one instrument which works on the above principle.

A boy of mass 30 kg is fitting at a distance of 2 m from the middle of a see-saw. Where should a boy of mass 40 kg sit so as to balance the see-saw?

A ball is placed on a compressed spring. When the spring is released, the ball is observed to fly away.
(i) What form of energy does the compressed spring possess?
(ii) Why does the ball fly away?

Give an experiment to verify the principle of moments.

Derive a relation between the S.I. and C.G.S. unit of force.

Calculate the work done when:
A car is moved on a rough road through 30 m against a frictional resistance of 75 N.