question_answer

What is the minimum acceleration \[({{a}_{o}})\] of the cart in the given figure so that block P will not  fall? (Assume coefficient of friction as\[\mu \]).

A) \[g/\sqrt{\mu }\]

B)  \[g/\mu \]

C)  \[2\mu g\]

D)  \[{{\mu }^{2}}g\]

Correct Answer: B

Solution :

 Due to frictional force, the block will be prevented from falling. From figure, we have \[N=m{{a}_{0}}\]                       ...(i) \[f=mg=\mu N\] ?(ii) Solving Eqs. (i) and (ii), we get \[mg=\mu (m{{a}_{0}})\] \[\Rightarrow \] \[{{a}_{0}}=g/\mu \]