$A$ ray of light is incident on a concave mirror after passing through the centre of curvature. What is the angle of incidence (in $°$)?

$A$ beam of light is incident through the holes on side $A$ and emerges out of the holes on the other face of the box as shown in the Figure. Which of the following could be inside the box?

Draw a ray diagram showing the path of rays of light when it enters with oblique incidence: $(i)$ from air into water; $(ii)$ from water into air.

When a plane mirror is rotated through a certain angle,the reflected ray turns through twice as much and the size of the image

Where is the object placed to observe it through a compound microscope?

The image formed by a concave mirror is real and of the same size. Where is the object placed?