JEE Main Test on Ray Optics

A beaker containing liquid is placed on a table, underneath a microscope which can be moved along a vertical scale. The microscope is focused, through the liquid onto a mark on the table when the reading on the scale is a.

It is next focused on the upper surface of the liquid and the reading is b. More liquid is added and the observations are repeated, the corresponding readings are c and d. The refractive index of the liquid is -

A parallel sided block of glass of refractive index 1.5 which is 36 mm thick rests on the floor of a tank which is filled with water (refractive index = 4/3). The difference between apparent depth of floor at A & B when seen from vertically above is equal to –

A single converging lens is held close to the eye for use as a mangnifying glass. For maximum magnifying power, the lens must be positioned so that the

A real image is formed by a convex lens, then it is connected with a concave lens, again the real image is formed. This will -

The refractive index n of a medium within a certain region x > 0, y > 0 changes with y till it aquires a value n_max. After it aquires the value n_max it remains constant. A light ray traveling in air along the x-axis, strikes the medium at a grazing angle and moves through the medium along a circular arc as shown in the figure. If angular deviation of the ray before it starts moving on a straight line is 60 º, then n_max is –