A) 49cm/s
B) 98 cm/s
C) 147 cm/s
D) 196 cm/s
Correct Answer: B
Solution :
Rate of change of momentum of bullet = weight of disc ie, \[m\frac{dv}{dt}=Mg\] \[5\times {{10}^{-3}}\times 10[v-(-v)]=10\times {{10}^{-3}}\times 9.8\] \[5(2v)=9.8\] \[v=\frac{9.8}{10}m/s\] \[=\frac{9.8}{10}\times 100\,cm/s\] \[=98\text{ }cm/s\]You need to login to perform this action.
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