The resistance of a galvanometer is 50 ohm and the maximum current which can be passed through it is 0.002 A. What resistance must be connected to it in order to convert it into an ammeter of range 0-0.5 A?

Correct option is A. 0.2 ohm
Let S be the shunt resistance required.
Current through galvanometer, Ig = 0.002 A
Current through shunt, Is = I - Ig = 0.5 - 0.002 = 0.498 A
Potential difference across galvanometer = Potential difference across shunt
Ig * G = Is * S
0.002 * 50 = 0.498 * S
S = (0.002 * 50) / 0.498
S = 0.1 / 0.498
S ≈ 0.2 ohm