Optics Mock Tests

In a Young double slit experiment, the fringe width is 0.5 mm. If the entire apparatus is immersed in water of refractive index 4/3, the new fringe width is:

In Young's double slit experiment, the fringe width is found to be 0.4 mm. If the whole apparatus is immersed in water of refractive index 4/3, the new fringe width will be:

A convex lens of focal length 15 cm forms a virtual image at 30 cm from the lens. The object distance is:

A converging lens of focal length f₁ is in contact with a diverging lens of focal length f₂ (|f₂| > f₁). The combination behaves as:

A telescope has magnifying power of 20. The focal length of the objective is 60 cm. The focal length of the eyepiece is:

A convex lens of focal length f is placed in contact with a concave lens of focal length −f. The combination acts as:

A convex lens of focal length f is used as a simple microscope. If the image is formed at the least distance of distinct vision D, the magnification is:

In Young's double slit experiment, the fringe width is found to be 0.4 mm. If the whole apparatus is immersed in water of refractive index 4/3, the new fringe width will be: