Question

What torque would have to be applied to a rod with a length of `4 m` and a mass of `3 kg` to change its horizontal spin by a frequency of `2 Hz` over `2 s`?

Answer 1

`L=24`

Explanation:

`alpha=L/I`
`"alpha: angular acceleration"`
`"L:torque"`
`"I=moment of inertia"`
`alpha =(Delta omega)/(Delta t)`
`alpha=2/2=1`
`1=L/I`
`L=I`
`L=1/12*m*l^2`
`"moment of inertia for a rod rotating around its center"`
`L=1/2*3*4^2=24`
`L=24`