Refraction & Lenses Mock Tests

A ray of light passes from air into a medium of refractive index 1.5. If the angle of incidence is 30°, the angle of refraction is:

A convex lens of focal length 20 cm and a concave lens of focal length 10 cm are placed in contact. The power of the combination is:

A convex lens of focal length f and refractive index μ is immersed in a liquid of refractive index μ_L < μ. The new focal length will be:

A convex lens of focal length 20 cm is made of material with refractive index 1.5. It is immersed in water of refractive index 4/3. The new focal length is approximately:

A convex lens of focal length 20 cm in air (refractive index 1.5) is immersed in water (refractive index 4/3). The new focal length of the lens in water will be approximately:

A converging lens of focal length 10 cm forms an image of an object placed at 15 cm from the lens. The image distance is:

A thin convex lens of focal length 0.5 m has a power of:

The refractive index of water is 4/3. The critical angle for total internal reflection at a water-air interface is approximately: