A) \[\frac{1}{2}m{{v}^{2}}\times \frac{m}{(m+M)}\]
B) \[\frac{1}{2}m{{v}^{2}}\times \frac{M}{(m+M)}\]
C) \[\frac{1}{2}m{{v}^{2}}\times \frac{(M+m)}{M}\]
D) \[\frac{1}{2}M{{v}^{2}}\times \frac{m}{(m+M)}\]
Correct Answer: A
Solution :
By conservation of momentum, \[mv+M\times 0=(m+M)V\] Velocity of composite block \[V=\left( \frac{m}{m+M} \right)\,v\] K.E. of composite block \[=\frac{1}{2}(M+m){{V}^{2}}\] \[=\frac{1}{2}(M+m)\,{{\left( \frac{m}{M+m} \right)}^{2}}{{v}^{2}}=\frac{1}{2}m{{v}^{2}}\left( \frac{m}{m+M} \right)\]
You need to login to perform this action.
You will be redirected in
3 sec
