Human Eye and Colourful World — Science STD 10 — Question

In the arrangement shown in Figure there are two coils wound on a non-conducting cylindrical rod. Initially the key is not inserted. Then the key is inserted and later removed. Then,

1. The deflection in the galvanometer remains zero throughout.
2. There is a momentary deflection in the galvanometer but it dies out shortly and there is no effect when the key is removed.
3. There are momentary galvanometer deflections that die out shortly; the deflections are in the same direction.
4. There are momentary galvanometer deflections that die out shortly; the deflections are in opposite directions.

Out of the following, the colour of light having the maximum wavelength is:

1. Violet.
2. Indigo.
3. Green.
4. Orange.

Which of the following is not caused by the atmospheric refraction of light?

1. Twinkling of stars at night.
2. Sun appearing higher in the sky than it actually is.
3. Sun becoming visible two minutes before actual sunrise.
4. Sun appearing red at sunset.

An induced current is produced when a magnet is moved into a coil. The magnitude of induced current does not depend on:

1. The speed with which the magnet is moved.
2. The number of turns of the coil.
3. The resistivity of the wire of the coil.
4. The strength of the magnet.

The amount of light entering the eye can be controlled by the:

 A cooler of 1500W, 200 volt and a fan of 500W, 200 volt are to be used from a household supply. The rating of fuse to be used is:

The person who is suffering from the following disease cannot donate eyes.

The speed of light will be minimum while passing through:

A spherical mirror to be made from a cut portion of:

In the case of hypermetropia: