Question

Two masses of 10 kg and 20 kg, are connected by a massless spring. A force of 200 N acts on the 20 kg mass. At the instant shown, the 10 kg mass has an acceleration of magnitude of $12m{s}^2$. The magnitude of the acceleration of the 20 kg mass is?

• A. $12m{s}^2$
• B. $4m{s}^2$
• C. $10m{s}^2$
• D. Zero

Answer 1

The correct option is B $4m{s}^2$

by balancing force on 20 kg block
$200-T=20a_1$
by balancing force on 10 kg block
T = 10x12
= 120
$200-120=20a_1$
$a_1=4m/s^2$