Question

Two bodies of masses m and M are attached to the two ends of a light string passing over a fixed ideal pulley (M >> m). When the bodies are in motion, the tension in the string is approximately 

(a) (M - m)g 

(b) mg 

(c) 2mg 

(d) (m/M)mg

Answer 1

Correct Answer is: (c) 2mg 

Mg - T = Ma, T - mg = ma.

∴ a = (M - m/ M + m)g.

T = mg + ma

= 2mg / 1 + m/M = 2 mg as M >> m.