Question

A spherical mirror and a thin spherical lens each have a focal length of -15cm.the mirror and the lens are likely to be (a)both concave (b)both convex (c)the mirror is concave and the lens is canvex (d)the mirror is convex but the lens is concave

Answer 1

Answer:

The thin spherical lens is a concave lens while the spherical mirror is a convex mirror

Explanation:

Since the focal length of the spherical mirror and the thin spherical lenses is negative, then it means a virtual image is formed on reflection.

Virtual images, or images that have negative focal lengths are formed from either:

1) A spherical convex mirror, or

2 A spherical concave lens

One characteristics of images formed on convex mirrors is that they are virtual with negative focal lengths

Images formed by concave lenses are also virtual and they have a negative focal length.

Therefore the mirror is a convex spherical mirror while the lens is a spherical concave lens.

Answer 2

ANSWER.......

Both concave........