Three equal weights of 3 kg each are hanging on a string passing over a frictionless pulley as shown in figure. The tension in the string between masses II and III will be (Take = `10m//sec^(2)`)

Options

A. 5 N
B. 6 N
C. 10 N
D. 20 N

Answer

D

Explanation

Three equal weights of 3 kg each are hanging on a string passing over a pulley as shown in figure. ltbRgt If a is the common acceleration.
`T-3g=3a` (For mass I)
`3g+T_(1)-T=3a` (For mass II)
`3g-T_(1)=3a` (For mass III)
Adding, above three equations
`3g=9a, a=g//3`
`T_(1)=3g-3a=3g-g=2g=20N`