When one light ray is reflected from a plane mirror with $30^{\circ}$ angle of reflection,the angle of deviation of the ray after reflection is $.....^{\circ}$

The figure shows two rays $A$ and $B$ being reflected by a mirror and emerging as $A'$ and $B'$. The mirror

If $\hat{n}_1, \hat{n}_2$ and $\hat{t}$ represent unit vectors along the incident ray, reflected ray, and normal to the surface respectively, then:

$A$ clock hung on a wall has marks instead of numbers on its dial. On the opposite wall there is a mirror,and the image of the clock in the mirror,if read,indicates the time as $8:20$. What is the actual time in the clock?

$A$ point object is kept in front of a plane mirror. The plane mirror is performing $SHM$ with an amplitude of $2 \ cm$. The plane mirror moves along the $x$-axis,and the $x$-axis is normal to the mirror. The amplitude of the mirror is such that the object is always in front of the mirror. The amplitude of the $SHM$ of the image is ....... $cm$.

$A$ ray of light makes an angle of $10^o$ with the horizontal above it and strikes a plane mirror which is inclined at an angle $\theta$ to the horizontal. The angle $\theta$ for which the reflected ray becomes vertical is......$^o$