JEE Main & Advanced Sample Paper JEE Main Sample Paper-43

  • question_answer
    A bar of mass \[m\] length \[l\] is in pure translator motion with its centre of mass velocity \[v\]. It collides with and sticks to another identical bar at rest as shown in figure. Assuming that after collision it becomes one composite bar of length \[2l\], the angular velocity of the composite bar will be

    A)  \[\frac{3v}{4l}\], anti-clockwise                       

    B)  \[\frac{4v}{3l},\]anti-clockwise

    C)  \[\frac{3v}{4l},\]clockwise

    D)  \[\frac{4v}{3l},\]clockwise

    Correct Answer: C

    Solution :

     By law of conservation of angular momentum \[\tan \theta =\frac{r}{h/2}\] \[\theta ={{45}^{o}},\]        \[r=\frac{h}{2}\] \[\theta ={{45}^{o}}\]         \[n'=\frac{v}{v-{{v}_{s}}}\times n\] (anti-clockwise) Not that clockwise or anti-clockwise rotation can only be determined here by the given figure.

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