To obtain $3$ images using two plane mirrors, they should be placed at an angle of ....... $^o$.

The coordinate of the image with respect to the origin $c$ will be:

$A$ man has a height of $180\, cm$ and his eyes are $10\, cm$ below the top of his head. He uses a plane mirror placed $1\, m$ away to see his full height from head to toe. What is the minimum required height of the plane mirror in $cm$?

$A$ light bulb is placed between two plane mirrors inclined at an angle of $60^{\circ}$. The number of images formed is:

The reflecting surface of a plane mirror is vertical. $A$ particle is projected in a vertical plane which is also perpendicular to the mirror. The initial velocity of the particle is $10 \, m/s$ and the angle of projection is $60^\circ$ with the horizontal. The point of projection is at a distance $5 \, m$ from the mirror. The particle moves towards the mirror. Just before the particle touches the mirror,the velocity of approach of the particle and its image is ...... $m/s$.

Two plane mirrors are at $45^{\circ}$ to each other. If an object is placed between them,then the number of images will be