Friction doubt!

A small block of mass $m$ is kept at the left end of a larger block of mass $M$ and length $l$ . The system is started towards right with an initial velocity $v$ . The friction coefficient between the road and the bigger block is $k$ and that between the blocks is $k/2$ . Find the time elapsed before the smaller block separates from the bigger block?

I am having hard time solving this , can somebody please help ,if possible with an FBD.

Thanks!

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Comments

@Deeparaj Bhat Please help!!!!

shivam mishra - 5 years ago

On the smaller block, the friction is towards the left (assuming the velpcity is towards the right).

On the bigger block, the friction at the contact surface of the smaller block is towards right (Newton's third law) and the friction at the ground surface is towards left.

Hope this helps!