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

An object $O$ is placed between two parallel plane mirrors $M_1$ and $M_2$. The distance of the object from $M_1$ is $6\,cm$ and from $M_2$ is $15\,cm$. The position of the $4^{th}$ image formed by mirror $M_1$ is:

$A$ ray of light is incident on a plane mirror at an angle of $30^\circ$. The deviation produced in the ray is....$^\circ$.

$A$ 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 the light is found to move through a distance $y$ on the scale. The angle $\theta$ is given by

$A$ small plane mirror is placed at the center of a spherical screen of radius $R$. Light rays are incident on the mirror. If the mirror is rotated at a frequency of $n$ revolutions per second,what will be the speed of the reflected light spot on the screen?

$A$ plane mirror makes an angle of $30^\circ$ with the horizontal. If a vertical ray strikes the mirror,find the angle between the mirror and the reflected ray.