If light ray is incident normally on face AB of a part of a prism, then for no emergent ray from second face AC [$\mu \to$refractive index of glass of prism]

(1) $\mu =\frac{2}{\sqrt{3}}$

(2) $\mu >\frac{2}{\sqrt{3}}$

(3) $\mu <\frac{2}{\sqrt{3}}$

(4) $\mu$ can have any value

A plane mirror is fixed in YZ-plane at x = 0. The velocity of a moving object is $\overrightarrow{v_0}=3\hat{i}+6\hat{j}+4\hat{k}$. The velocity of the image relative to a stationary observer will be:

1.  $3\hat{i}-6\hat{j}-4\hat{k}$

2.  $3\hat{i}-6\hat{j}+4\hat{k}$

3.  $-3\hat{i}+6\hat{j}+4\hat{k}$

4.  $-3\hat{i}-6\hat{j}-4\hat{k}$

If there is no emergent light through a prism of refracting angle \(60^{\circ},\) whatever may be the angle of incidence, then the minimum value of the refractive index of the material of the prism is:

If the space between two convex lenses of glass in the combination shown in the figure below is filled with water, then

1.  The focal length of the system will decrease

2.  The focal length of the system will increase

3.  Power of the system will increase

4.  Power of the system will become infinite  

A prism of refracting angle $30°$, has one of the refracting faces polished. A beam of light incident on the other refracting face with i = $60°$ will retrace its path, if the refractive index of prism would be

1.  $\sqrt{2}$

2.  $\sqrt{3}$

3.  $\sqrt{5}$

4.  $\sqrt{7}$

To form an achromatic combination, two lenses of focal length X and Y and dispersive power A and B respectively, are kept in contact. Which of the following is correct?

1.  A = C, B = C/2; X = 2Y

2.  A = C, B = C/2; X = -2Y

3.  A = C, B = 2C; X = 2Y

4.  A = C, B = 2C; X = -2Y 

In a glass ($\mu =1.5$) sphere of radius 10 cm, there is an air bubble B at distance 5 cm from C. The distance of bubble from the surface of the sphere (i.e. point A) as observed from point P in the air will be

(1) 4.5 cm

(2) 20.0 cm

(3) 9.37 cm

(4) 6.67 cm

A concave lens is made of three layers of glass of three different materials as shown in the furure. A point object is placed on its axis. Number of images of the object is -

1. 2

2. 3

3. 4

4. 1

An object is placed at a distance of 20 cm from the thin lens as shown in the figure. The points $C_1$ and $C_2$ denote centres of curvature. The magnification produced by the lens is (Refractive index of glass is 1.5)

1.  -2

2.  +2

3.  -1/2

4.  +1/2