Light enters at an angle of incidence in a transparent rod of refractive index n. For what value of the refractive index of the material of the rod, will the light, once entered into it, not leave it through its lateral face whatsoever be the value of the angle of incidence?
1. $n$ $>\sqrt{2}$
2. 1.0
3. 1.3
4. 1.4

A tall man, of height \(6\) feet, wants to see his full image. The required minimum length of the mirror will be:

A bubble in glass slab (µ = 1.5) when viewed from one side appears at 5 cm and 2 cm when viewed from the other side. Thickness of the slab is:

1. 3.75 cm

2. 3 cm

3. 10.5 cm

4. 2.5 cm

A beam of light composed of red and green rays is incident obliquely at a point on the face of a rectangular glass slab. When coming out on the opposite parallel face, the red and green rays emerge from:

The refractive index of the material of a prism is $\sqrt{2}$ and its refracting angle is \(30^{\circ}\). One of the refracting surfaces of the prism is made a mirror inwards. A beam of monochromatic light entering the prism from the other face will retrace its path after reflection from the mirrored surface if its angle of incidence on the prism is:
1. \(60^{\circ}\)
2. \(0^{\circ}\)
3. \(30^{\circ}\)
4. \(45^{\circ}\)

For the given incident ray as shown in the figure, in the condition of the total internal reflection of this ray, the minimum refractive index of the prism will be:

1. $\frac{\sqrt{3}+1}{2}$

2. $\frac{\sqrt{2}+1}{2}$

3. $\sqrt{\frac{3}{2}}$

4. $\sqrt{\frac{7}{6}}$

If refractive index of a prism is \(\mathrm{cot(A/2)}\), then the minimum angle of deviation is:
1. \(180^{\circ}-A\)
2. \(180^{\circ}-2A\)
3. \(90^{\circ}-A\)
4. \((A/2)\)

A bulb is located on a wall. Its image is to be obtained on a parallel wall with the help of a convex lens. If the distance between parallel walls is 'd' then the required focal length of the lens placed in between the walls is:

In a compound microscope, the magnification is \(95\), the distance of the object from the objective lens is \(\frac{1}{3.8}~\text{cm}\) and the focal length of the objective is \(\frac{1}{4}~\text{cm}\). What is the magnification of the eyepiece when the final image is formed at the least distance of distinct vision?
1. \(5\)
2. \(10\)
3. \(100\)
4. none of the above

A disc is placed on the surface of a pond which has a refractive index of $\frac{5}{3}$. A source of light is placed 4 m below the surface of the liquid. Find The minimum radius of a disc so that light does not come out from it.
1.  ∞
2.  3 m
3.  6 m
4.  4 m