Question

Calculate the angular momentum that keeps an 80-kg person sitting on the edge of a horizontal rotating platform when the person sits 2 m from the center of the platform and has a tangential speed of 3 m/s

Answer 1

Tangential speed is 0.68 m/s

Step-by-step explanation:

It is given that,

Mass of the beetle, m = 0.023 kg

It is placed at a distance of 0.15 m from the center of record i.e. r = 0.15 m.

If it takes 0.070 n of force to keep the beetle moving in a circle on the record i.e. centripetal force acting on it is, F = 0.070 N

We have to find the tangential speed of the beetle. The formula for centripetal force is given by :

v is tangential speed

v = 0.675 m/s

or

v = 0.68 m/s

Hence, the correct option for tangential speed is (A).

Step-by-step explanation:

Answer 2

`L=480\ kg-m^2/s`

Step-by-step explanation:

Given that,

Mass of a person, m = 80 kg

The distance from the centre of the platform, r = 2 m

The tangential speed of the platform, v = 3 m/s

We need to find the angular momentum of the person. The formula for the angular momentum is given by :

`L=mvr\\\\L=80* 3* 2\\\\L=480\ kg-m^2/s`

So, the required angular momentum is equal to
`480\ kg-m^2/s`.