$A$ light ray is incident perpendicular to the plane of a mirror. The angle of reflection will be ......$^o$.

Two plane mirrors are inclined at an angle of $72^{\circ}$. The number of images of a point object placed between them will be

The rear window of a car has a size of $120 \, cm \times 45 \, cm$. The driver sits at a distance $L = 2 \, m$ from the rear window. What should be the minimum size of a flat mirror,hanging at a distance of $0.5 \, m$ in front of the driver,so that he has the best view of the road situation behind the car?

$A$ ball is projected from the top of a table with an initial speed $u$ at an angle of inclination $\theta$ with the horizontal. What is the motion of the image of the ball with respect to the ball?

$A$ plane mirror makes an angle of $30^\circ$ with the horizontal. $A$ vertical ray is incident on the mirror. What is the angle between the mirror and the reflected ray in degrees?

Two plane mirrors are placed at an angle of $60^\circ$. $A$ horizontal light ray is reflected by the first mirror and then by the second mirror. The total deviation will be ........... $^\circ$.