Laws Of Motion Question 426
Question: The system is released from rest. The spring gets elongated
Options:
A) for M > m
B) for M > 2 m
C) for $ M>\frac{m}{2} $
D) for any value of M
Show Answer
Answer:
Correct Answer: D
Solution:
[d] Net pulling force on the system is $ Mg+mgmg $ or Mg.
Total mass being pulled is$ M+2m. $ Hence, acceleration of the system is $ \sigma =\frac{Mg}{M+2m} $
Now since a < g. There should be an upwards force on m so that its acceleration becomes less than g.
Hence for any value of m spring will be elongated.
