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

A physical balance has its arms of length 60 cm and 40 cm. What weight kept on pan of the longer arm will balance an object of weight 100 gf kept on other pan?

A uniform metre rule of mass 100 g is balanced on the fulcrum at mark 40 cm by suspending an unknown mass m at the mark 20 cm.

1. Find the value of m.
2. To which side the rule will tilt if the mass m is moved to the mark 10 cm?
3. What is the resultant moment now?
4. How can it be balanced by another mass of 50 g?

When sunlight enters the earth’s atmosphere, state which colour of light is scattered

1. the most and
2. which the least.

The danger signal is red. Why?

How would the sky appear when seen from the space (or moon)? Give reason for your answer.

What characteristic property of light is responsible for the blue colour of the sky?

The colour of sky, in direction other than of the sun, is blue. Explain.

Why does the sun appear red at sunrises and sunset?

The clouds are seen white. Explain

In white light of sun, maximum scattering by the air molecular present in the earth’s atmosphere is for ______.

What are damped vibrations? How do they differ from free vibrations? Give one example of each.

The following diagram shows the displacement – time graph of the vibrating body.

1. Name the kind of vibrations
2. Give one example of such vibrations.
3. Why is the amplitude of vibrations gradually decreasing?
4. What happens to the vibrations of the body after some time?

A tuning fork is set into vibration in air. Name the kind of vibrations it executes.

Draw a sketch showing the displacement of a body executing damped vibrations against time.

What is a fixed pulley?

What is the ideal mechanical advantage of a single fixed pulley? Can it be used as a force multiplier?

Name the pulley which has no gain in mechanical advantage. Explain, why is such a pulley then used?

What is the velocity ratio of a single fixed pulley?

In a single fixed pulley, if the effort moves by a distance x downwards, by what height is the load raised upwards?

Draw a circuit diagram using the dual control switches to light a staircase electric light and explain its working.