Question

a man is running towards a plane mirror at a speed of 10 m/s how fast does he see himself running towards his image?​

Answer 1

$20 \: m {s}^{ - 1}$

Explanation:

$\boxed{speed \: \: in \: \: mirror = 2 \times real \: \: speed} \\ \: \: \: \: \: \: \: \: = 2 \times 10 \: m {s}^{ - 1} \\ = 20 \: m {s}^{ - 1}$