Answer:
Explanation:
Given that,
We have five children.
Each of mass m =30kg
They sit on a merry go round
Mass of Merry go round M= 150kg
Radius of Merry go round is r =2m
Four children sit at the edge of the merry go round but one child sit at the centre.
The four child that sit at the edge are 2m from the centre of the merry go round but the one at the centre is 0m from the centre
Moment of inertia?
Moment of inertia is given as
I=Σmi•ri²
For the question, the moment of inertia is the combination of inertial of child and the merry go round
I= I(merry go round) + I(four child)+ I(last child)
The merry go round is assumed to be a solid cylinder, so it is going to have the moment of inertia of solid cylinder
Then,
I(merry go round ) =½ Mr²
Also, Four of the child has the same moment of inertia, they are 2m form the centre of the merry go round why the last child has no moment of inertia
I= I(merry go round) + I(four child) +I(last child )
I= ½Mr² + 4mr² + mr'²
I = ½ × 150 ×2² + 4×30×2² + 30×0²
I = 300 +480+0
I = 780 kgm²