Physics- Ray Optics and Optical Instruments

Two beams of red and violet color are made to pass separately through a prism (angle of the prism is 60 Degree). In the position of minimum deviation, the angle of refraction will be

Two lenses of focal lengths 20 cm and - 40 cm are held in contact. The image of an object at infinity will be formed by the combination at

Which of the following forms a virtual and erect image for all positions of the object?

A convex lens is dipped in a liquid whose refractive index is equal to the refractive index of the lens. Then its focal length will

Mirage is a phenomenon due to

Critical angle of glass is θ2 and that of water is θ2. The critical angle for water and glass surface would be (μg = 3/2, μw = 4/3)

For a total internal reflection, which of the following is correct?

A rod of length 10 cm lies along the principal axis of a concave mirror of focal length 10 'em in such a way that its end closer to the pole is 20 cm away from the mirror. The length of the image is

The astronomical telescope consists of objective and eyepiece. The focal length of the objective is

A diver at a depth 12 m inside water (p = 4/3) sees the sky in a cone of semi-vertical angle