The system shown in figure is in equilibrium. The spring is light, the acceleration of both the blocks (in $m / s^{2}$ ) just after the string S is cut is

Question

The system shown in figure is in equilibrium. The spring is light, the acceleration of both the blocks (in m / s 2 ) just after the string S is cut is

TestHub · Accepted Answer

Before cutting, the spring force on B is $k x = 2 g = 20 N$ and the string tension is $T = 2 g + k x = 4 g = 40 N$ .

Just after the string is cut, the tension vanishes but the spring force stays (the spring cannot change length instantly).

Block A: net force $= 2 g + k x = 4 g = 40 N$ downward, so $a_{A} = \frac{40}{2} = 20 m/ s^{2}$ .

Block B: spring force $k x = 2 g$ balances weight, net force $0$ , so $a_{B} = 0$ .

Physics - NLM Question with Solution | TestHub

Options:

Doubts & Discussion