Question

a wire is wounded in hollow cylinder of radius 40 cm.mass of cylinder is 3 kg. force of 30 N is applied on wire then angular momentum of body​

Answer 1

Given:

A wire is wounded in hollow cylinder of radius 40 cm.mass of cylinder is 3 kg. force of 30 N is applied on wire.

To find:

Angular momentum of body.

Calculation:

We know that Torque is the instantaneous rate of change of angular momentum of a body.

$\sf{ \therefore \: \tau = \dfrac{\Delta L}{\Delta t} }$

$\sf{ = > f \times r \: = \dfrac{\Delta L}{\Delta t} }$

Putting available values in SI units:

$\sf{ = > 30\times \dfrac{40}{100} \: = \dfrac{ L - 0}{t - 0} }$

$\sf{ = > 3 \times 4 \: = \dfrac{ L }{t } }$

$\sf{ = > 12\: = \dfrac{ L }{t } }$

$\sf{ = > L = 12t }$

So, final answer is:

$\boxed{ \sf{final \: angular \: momentum = L = 12t }}$