Question

A constant force f has been applied upon plank of mass m . upon plank a thin circular wheel of mass m and radius r has placed there is no. slipping be plank and wheel. the acc of plank​

Answer 1

The acc of plank​ is $\frac{F}{2m}$.

Explanation:

1. In this case

  mass of plank = m (kg)

  mass of wheel = m (kg)

  force apply on plank = F (N)

  There are no slipping between plank and wheel. Its means there are friction between plank and wheel.

  Assuming there are no friction between plank and ground surface on plank is kept.

2. Now from Newton's second law

    $\sum F=\sum m\times a$   ...1)

  Where

   $\sum F$ = net force on object =F

   $\sum m$ = total mass of object= m + m= 2m

  a = acceleration of object

3. from equation 1)

   F = 2m×a

  So

  Acceleration (a)= $\frac{F}{2m}$