Alarge wooden turntable in the shape of a flat uniform disk has a radius of 2.00 m and a total mass of 120 kg. the turntable is initially rotating at 3.00 rad> s about a vertical axis through its center. suddenly, a 70.0-kg parachutist makes a soft landing on the turntable at a point near the outer edge. (a) find the angular speed of the turntable after the parachutist lands. (assume that you can treat the parachutist as a particle.) (b) compute the kinetic energy of the system before and after the parachutist lands. why are these kinetic energies not equal

a)1.385  rad/s

b) Before: 1080 J. After 498.46 J

Explanation:

The moments of inertia of the turn table, with the shape of uniform disk is:

The angular momentum of the turn table before the impact is

The moments of inertia of the system after the impact is (treating the parachute man is a point particle)

According to angular momentum conservation law:

(b) Before the impact:

After the impct

The kinetic energies are not equal because the impact is causing the turn table to lose energy.

find the surface area of the sphere to the nearest square unit. use a calculator.

a. 254 in.2

b. 64 in.2

c. 127 in.2

d. 1,018 in.2

+15-35=-20

going in opposite directions