NEET Solved Paper 2017 Question 16
Question: Two blocks A and B of masses 3m and m respectively are connected by a massless and inextensible string. The whole system is suspended by a massless spring as shown in figure. The magnitudes of acceleration of A and B immediately after the string is cut, are respectively
Options:
A) $ \frac{g}{3},\frac{g}{3} $
B) $ g,\frac{g}{3} $
C) $ \frac{g}{3},g $
D) $ g,g $
Show Answer
Answer:
Correct Answer: C
Solution:
- Sol. Before the string is cut
$ \Rightarrow $ $ kx=T+3mg $ -(i)
$ \Rightarrow $ $ T=mx $ - (ii)
$ \Rightarrow $ $ kx=4mg $ After the string is cut, T = 0 $ a=\frac{kx-3mg}{3m} $ $ a=\frac{4mg-3mg}{3m} $ $ a=\frac{g}{3}\uparrow $
