A point source of light B is placed at a distance L in front of the centre of a mirror of width d hung vertically on a wall. A man walks in front of the mirror along a line parallel to the mirror at a distance 2L from it as shown. The greatest distance over which he can see the image of the light source in the mirror is

(1) d/2                                     

(2) d

(3) 2d                                       

(4) 3d

Two plane mirrors, \(A\) and \(B\) are aligned parallel to each other, as shown in the figure. A light ray is incident at an angle of \(30^\circ\) at a point just inside one end of \(A\). The plane of incidence coincides with the plane of the figure. The maximum number of times the ray undergoes reflections (excluding the first one) before it emerges out is:
   
1. \(28\)                     
2. \(30\)
3. \(32\)         
4. \(34\)

A room (cubical) is made of mirrors. An insect is moving along the diagonal on the floor

such that the velocity of image of insect on two adjacent wall mirrors is $10 cm{s}^{-1}$. The

velocity of image of insect in ceiling mirror is

1. 10 $cm{s}^{-1}$                           

2. 20 $cm{s}^{-1}$

3. $\frac{10}{\sqrt{2}}cm{s}^{-1}$                          

4. $10\sqrt{2}cm{s}^{-1}$

If an object moves towards a plane mirror with a speed v at an angle $\theta$ to the perpendicular to the plane of the mirror, find the relative velocity between the object and the image

1. v                                           

2. 2v

3. 2v cos $\theta$                                    

4. 2v sin $\theta$

A beam of light from a source L is incident normally on a plane mirror fixed at a certain distance x from the source. The beam is reflected back as a spot on a scale placed just above the source L. When the mirror is rotated through a small angle $\theta$, the spot of light is found to move through a distance y on the scale. The angle $\theta$ is given by 

(1) $\frac{y}{2x}$

(2) $\frac{y}{x}$

(3) $\frac{x}{2y}$

(4) $\frac{x}{y}$