Question

Two forces F1​ and F2​ are applied on a spool of mass M and moment of inertia l about an axis passing through its centre of mass.The ratio F2​F1​​ so that the force of friction is zero is xMr2−ll+2Mt2​. Find x. Given that l<2Mr2

​

Answer 1

a=Rα by applied forces

∴

M

F

1

+F

2

=2r[

I

F

1

(2r)−F

2

(r)

]

Solving these two equations we get,

F

2

F

1

=

4Mr

2

−I

I+2Mr

2