$A$ cubical room is formed with $6$ plane mirrors. An insect moves along the diagonal of the floor with uniform speed $v_0$. The speed of its image in two adjacent walls,parallel to the walls,is $20\sqrt{2} \ cm/s$. Then the speed of the image formed on the roof with respect to the ground is ...... $cm/s$.

Two vertical parallel mirrors $A$ and $B$ are separated by $10\,cm$. $A$ point object $O$ is placed at a distance of $2\,cm$ from mirror $A$. The distance of the second nearest image behind mirror $A$ from the mirror $A$ is $.........\,cm$.

An object is placed at a distance of $12\,cm$ in front of a plane mirror. $A$ virtual and erect image is formed by the mirror. Now,the mirror is moved by $4\,cm$ towards the stationary object. The distance by which the position of the image would be shifted is:

$A$ person runs with a speed $u$ towards a bicycle moving away from him with speed $v$. The person approaches his image in the mirror fixed at the rear of the bicycle with a speed of:

The light reflected by a plane mirror may form a real image:

$A$ point source of light $S$,placed at a distance $60 \,cm$ in front of the centre of a plane mirror of width $50 \,cm$,hangs vertically on a wall. $A$ man walks in front of the mirror along a line parallel to the mirror at a distance $1.2 \,m$ from it (see in the figure). The distance between the extreme points where he can see the image of the light source in the mirror is $\ldots \ldots \ldots \,cm.$