Light Test - 8...

Two beams of light; one red and the other green fall on the same spot on a white screen. The colour on the screen will appear to be

Which of the following statements is correct?

The totally dark part of the shadow is called

A picture seen on the screen of a pinhole camera is

If a man approaches a plane mirror at the rate of 2 km/hr, then his image would approach him at the rate of

To see a full size image of ourselves, we should use a plane mirror of ____ times the height of ourselves.

f = -R/2; this relation indicates that mirror is

A concave mirror of focal length f produces an image m times the size of the object. If the image is real, then the distance of the object from the mirror is

If refractive index for glass is 1.5, and the velocity of light in vacuum is 3.0 10⁸ m/sec, the time taken by the light in travelling a distance of 300 m in glass will be

When angle of incidence in a denser medium is equal to critical angle, the angle of refraction is

We always get real image in a convex lens if the object is situated beyond

An object is placed in front of a convex mirror between f and 2f. The image formed must be

A ray of light strikes a thick parallel sided glass slab with an angle of incidence of 40°. The angle of the beam emerging from the other side of the slab with the normal is

When will the magnifying power of an astronomical telescope be increased?

If f₀ and f_e are the focal lengths of the objective and eye – piece, respectively for a telescope, the magnifying power of the telescope will be

Dispersion produced by a prism depends upon

Coloured band of light obtained by dispersion of white light is called

The sky appears blue because the earth's atmosphere

In a room, artificial rain is produced at one end and a strong source of white light is switched on at the other end. To observe the rainbow, an observer must

An eye specialist prescribes spectacles having a combination of convex lens of focal length 50 cm in contact with a concave lens of focal length 25 cm. The power of this combination of lenses (in dioptre) is