The angle made by the incident ray of light with the reflecting surface is called:

$A$ mirror is placed at a distance of $60 \ m$ from the base of a tower. The angle between the top of the tower and the top of its image is $90^o$. Find the height of the tower in $m$.

Digital movie projectors work on the principle of

When a plane mirror is placed horizontally on a level ground at a distance of $60 \ m$ from the foot of a tower,the top of the tower and its image in the mirror subtend an angle of $90^\circ$ at the eye. The height of the tower will be.....$m$.

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

Two plane mirrors are parallel to each other and an object $O$ is placed between them. Then the distance of the first three images from the mirror $M_2$ will be (in $cm$):