When a man moves toward a plane mirror at a speed of 6m/s; the distance the man and his image increased at a speed of?

A. 2 m/s
B. 4 m/s
C. 12 m/s
D. 14 m/s

Correct Answer: Option C

Explanation

d = y, s = 6 m/s (The Man & Plane Mirror)

d – δy, s = (5 &ndash ;6) m/s (The Man and Image)

d2 ÷ s1 = d2 ÷ s2, y ÷ 6 = 2y ÷ s + 6

Y (s + 6) = 2y × 6

s + 6 = 12

So = 12 – 6 = 6

Since S + 6 = 0

Then, S = 6 (substitute the value of S i.e S = 6)

Into S + 6 = 0

∴So = S + 6 = 6 + 6 = 12 m/s

∴ S = 12 m/s