Answer is A, I understand why the lense\'s f is increased, but why is the mirror
ID: 1519531 • Letter: A
Question
Answer is A, I understand why the lense's f is increased, but why is the mirror not affected. Could someone explain and perhaps draw a diagram?
20. A convex lens and a convex mirror are constructed to have the same focal lengths in air. When they are submerged in water, what can you conclude about the underwater focal lengths?
(a) fmirror is unchanged, flens is increased.
(b) flens is unchanged, fmirror is increased.
(c) fmirror is decreased, flens is increased.
(d) fmirror is decreased, flens is decreased.
(e) fmirror is unchanged, flens is unchanged.
Explanation / Answer
The mirror is not affected because it takes reflexion rays when you have a ray in a medium it doesn't change direction the reflexion law is still valid. This is different from a lens in a lens the rays travel from water to glass and the it goes to water again here the light change its speed.