Light Test - 3...

When an ultraviolet radiation is incident on a surface, no photoelectrons are emitted. If a second beam causes photo-electrons to be ejected, it may consist of

A red cross on a white background, when seen through a red filter,

A bird flying high up in air does not cast shadow on the ground because

A man is 170 cm tall. He wants to see his full length image in a plane mirror. If his eyes are at a height of 164 cm from the ground, minimum length of the plane mirror should be

Which of the following capital English letters does not show lateral inversion?

In a looking mirror or a window pane, you find that your face appears larger than normal. The mirror or window pane is

If the angle of incidence is equal to the critical angle, the angle of refraction will be

A convex lens of focal length 1 metre is placed in contact with another concave lens of equal focal length. What is the focal length of the new lens formed?