Question

A block of mass m is placed in contact with another block of mass M as shown in the figure.The coefficient of friction between the blocks is $\mu$ . with what acceleration the block M should move so that the block m does not slide down?

• A. $\mu g$
• B. $\mu$
• C. ${\mu }^2/g$
• D. $g/{\mu }^2$

Answer 1

The correct option is A $\mu g$

Given,

The coefficient of friction, $\mu$

The condition of non-sliding, acceleration of both $M\&m$ is equal.

So, inertial acceleration of block $=a$

Friction force on block m $\ge$ inertial acceleration of block m

$\mu mg\ge ma$

$a\le \mu g$

To avoid sliding acceleration of block acceleration $a\le \mu g$.