Sunbeam makes an angle θ = 4 0 ∘ with the surface of the Earth. At what angle to the horizontal should we place a flat mirror so that a ray of sunlight after reflection falls on the bottom of a deep w

Question

Sunbeam makes an angle θ = 4 0 ∘ with the surface of the Earth. At what angle to the horizontal should we place a flat mirror so that a ray of sunlight after reflection falls on the bottom of a deep well?

TestHub · Accepted Answer

The reflected ray is vertical (downward).

Angle between incident and reflected ray $= 4 0^{\circ} + 9 0^{\circ} = 13 0^{\circ}$ , so $i = r = 6 5^{\circ}$ .

Angle between the incident ray and the mirror $= 9 0^{\circ} - 6 5^{\circ} = 2 5^{\circ}$ .

Angle of mirror with horizontal $= 4 0^{\circ} + 2 5^{\circ} = 6 5^{\circ}$ .

Physics - Geometrical Optics Question with Solution | TestHub

Options:

Doubts & Discussion