ICSE ICSE Class 8 - CISCE Question Bank Solutions

Define the term energy.

State the S.I. unit of energy.

Define 1 joule of energy.

How is work related to energy?

What are the two kinds of mechanical energy?

Match the Following

What do you understand by refraction of light?

Give reasons for the following. No work is done if a man is pushing against a wall.

Give reasons for the following A teacher moving around in the class is doing work but a child standing and reading a book is not doing any work.

Draw a diagram showing the refraction of a light ray from water to glass. Label on it the incident ray, the angle of incidence (/), and the angle of refraction (r)

A force of 30 N acts on a body and moves it through a distance of 5 m in the direction of force. Calculate the work done by the force.

A man lifts a mass of 20 kg to a height of 2.5 m. Assuming that the force of gravity on 1 kg mass is 10 N, find the work done by the man.

A body, when acted upon by a force of 10 kgf, moves to a distance 0.5 m in the direction of force. Find the work done by the force. Take 1 kgf = 10 N.

Draw suitable diagrams to illustrate how a beam of light incident parallel to the principal axis is reflected by:
(a) a concave mirror, and (b) a convex mirror

The diagram (figure) given below shows two parallel rays 1 and 2 incident on (a) a concave mirror, (b) a convex mirror. Draw the reflected rays and mark the focus by the symbol F.

Electric work done per unit time is ____________.

The temperature of a substance remains unaffected during its change of state.

Ice melts at 100°C.

Water at 100°C has more heat than the steam at 100°C.

Evaporation of a liquid causes cooling.