Question 6: Laws of Motion

Question

In the figure, blocks A and B of
masses 2m and m are connected
with a string and system is hanged
vertically with the help of a spring.
Spring has negligible mass. Find
out magnitude of acceleration of
masses 2m and m just after the
instant when the string is cut
![](https://app-content.cdn.examgoal.net/fly/@width/image/jaoe38c1m3o07f86/bc246d36-0484-4bfe-98f0-38d76e2d3432/abbf6760-a635-11ef-a300-b723d4598e73/file-jaoe38c1m3o07f87.png?format=png)

Accepted Answer

When the system is in equilibrium, then the
spring force is 3 mg. When the string is cut, then
net force on block A
$=3mg-2mg=mg$
Hence, acceleration of block A at that instant
$a=\frac{	ext { force on block } A}{	ext { mass of block } A}=\frac{m g}{2 m}=\frac{g}{2}$
When string is cut, then block $B$ falls freely with an acceleration equal to $g$.

Answer

$g, g$

Answer

$g, \frac{g}{2}$

Answer

$\frac{g}{2}, g$

Answer

$\frac{g}{2}, \frac{g}{2}$

Laws of Motion

In the figure, blocks A and B of masses 2m and m are connected with a string and system is hanged vertically with the help of a spring. Spring has negligible mass. Find out magnitude of acceleration of masses 2m and m just after the instant when the string is cut

Choose the correct answer: