Two blocks of masses 40 kg and 20 kg are connected by a wire that has a linear mass density of `1 g//m`. These blocks are being pulled across horizontal frictionless floor by horizontal force F that is applied to 20 kg block. A transverse wave travels on the wave between the blocks with a speed of `400 m//s` (relative to the wire). the lmass of the wire is negligible compared to the mass of the blocks. the magnitude of F is

Options

A. 160 N
B. 240 N
C. 320 N
D. 400 N

Answer

b

Explanation

Tension T in the wire `=v^(2)p=(400)^(2)xx10^(-3)=160 N`
Force applied
`F=(T(m_(1)+m_(2)))/(m_(1))`

`=160xx((40+20))/(40)=240 N`