1. The lens equation \(\frac{1}{f}=\frac{1}{v}-\frac{1}{u}\)

2. u = -36, f = 10

\(\frac{1}{v}-\frac{1}{u}=\frac{1}{f}\)

i.e. v = \(\frac{36\times10}{46}\) = 7.8 cm

If object is moved 10 cm towards the lens we can find position

u = -26, f = 10

v = 7.2 cm

Speed = \(\frac{7.8-7.2}{2}\) = 3 cm/sec

3. Comparing speed of object and image we can arrive at conclusion that the argument of man is false, speed of image is different from speed of object.