$A$ concave mirror can be used to obtain a parallel beam of light from a small lamp.

Where will the image of an object placed at the centre of curvature of a concave mirror form?

The figure below shows a lens treated as a combination of two prisms and a glass block. $(i)$ Name the lens formed by the combination. $(ii)$ Is the lens converging or diverging? $(iii)$ Draw the refraction of two incident rays to illustrate the property of the lens mentioned by you in part $(ii).$

Where will the image be formed by a concave mirror when an object is placed between the pole and the focus point of the mirror?

What is the lens placed near the eye in a compound microscope called?

Magnification is the ratio of which of the following?