# Homework Help: Rotational mechanics

1. Nov 23, 2013

### allyferrell

1. The problem statement, all variables and given/known data

A plank having mass 3.7 kg rides on top of two identical solid cylindrical rollers each having radius 5.5 cm and mass 2.9 kg. The plank is pulled by a constant horizontal force of 6 N applied to its end and perpendicular to the axes of the cylinders(which are parallel). The cylinders roll without slipping on a flat surface. There is also no slipping between the cylinders and the plank.

1.) Find the acceleration(linear) of the plank(m/s^2).

2.) Find the frictional force acting acting on the plank(N).

M=3.7 kg
m=2.9 kg
r=.055 m
F=6 N
α = angular acceleration
a=linear acceleration

2. Relevant equations

τ=Fr
Ʃτ=Iα
F=ma
Frictional force(static) = force applied

3. The attempt at a solution
1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

2. Nov 23, 2013

### TSny

Hello, alleyferrell. Welcome to PF!

As stated in the rules of the forum, you'll need to fill out part 3 ("Attempt at a solution") before any help can be given. So, show us what you've got so far.