2. Solved Papers
  3. CMC Medical

CMC Medical CMC-Medical VELLORE Solved Paper-2011

  • question_answer
    A disc of mass 10 g is kept horizontally in air by firing bullets of mass 5 g each at the rate of 10 per second. If the bullets rebound with the same the same speed, what is the velocity with which the bullets are fired?

    A)  49 cm/s              

    B)  98 cm/s

    C)  147 cm/s            

    D)  196 cm/s

    E)  208 cm/s

    Correct Answer: B

    Solution :

                     Rate of change of momentum of bullets = weight of disc i.e.,        \[m\frac{dv}{dt}=mg\] \[5\times {{10}^{-3}}\times 10\,[v-(-v)]=10\times {{10}^{-3}}\times 9.8\]                 \[5(2v)=9.8\]                 \[v=\frac{9.8}{10}m\text{/}s\]                 \[=\frac{9.8}{10}\times 100\,cm\text{/}s\]                 \[=98\,cm\text{/}s\]


You need to login to perform this action.
You will be redirected in 3 sec spinner