Question

A convex lens is also called a
A) Diverging lens
B) Converging lens
C) Cylindrical lens
D) Opaque lens

Answer 1

Hint: Convex lens is a lens used in telescopes to gather as much light coming from the night sky. Also in most cases, a convex lens forms real images. A convex lens is used in telescopes to gather as much light as possible and focus it at a particular point.
Complete step by step answer:
The convex lens is a lens whose faces are curved outward. It usually forms a real image most of the time inverted. A good property of the convex lens is that it can take all the light falling on it from infinity (light coming from a very far away source) and focus it to a particular point. This focusing of light rays coming towards it from infinity is known as convergence.

For example, our eyes cannot see the neighbouring planets or its satellites because the light-gathering power of our eyes is less. So if we use a telescope with a convex lens which has a huge aperture, it will capture most of the light coming to it and focus it on a mirror or a screen so that we can see the astronomical object in our solar system and outside it.
So the answer to the question is option (B)-Converging lens.
Note:
If the light coming from infinity fails to converge at a point on the axis called the focus, we say that the lens contains aberrations. Aberrations are imperfections in the image formation of a lens due to many reasons.
The distance between the lens and the focal point where all the rays converge is known as the focal length of the lens. For a convex lens, the focal length is positive while for a concave lens it is negative.