Answer:
im pretty sure the answer is c please mark me brainliest
Answer:
1. Emma standing on top of mountain
Since she is at the rest position and at some height from the ground so here energy is due to gravitational potential energy
So we have
gravitational potential energy

2. Emma jumping down from mountain top
Due to free fall Emma will start moving with some speed in downwards direction so here we have

motion energy
3. tension in rope at Emma’s lowest position
Due to stretch in the rope here position come to the lowest end and speed comes to zero so whole energy is converted into elastic potential energy

elastic potential energy
4. Emma bouncing back
Due to bouncing back she will again have its kinetic energy with some speed upwards

motion energy
Answer:
Power, P = 924.15 watts
Explanation:
Given that,
Length of the ramp, l = 12 m
Mass of the person, m = 55.8 kg
Angle between the inclined plane and the horizontal, 
Time, t = 3 s
Let h is the height of the hill from the horizontal,


h = 5.07 m
Let P is the power output necessary for a person to run up long hill side as :



P = 924.15 watts
So, the minimum average power output necessary for a person to run up is 924.15 watts. Hence, this is the required solution.
Answer:
1) 883 kgm2
2) 532 kgm2
3) 2.99 rad/s
4) 944 J
5) 6.87 m/s2
6) 1.8 rad/s
Explanation:
1)Suppose the spinning platform disk is solid with a uniform distributed mass. Then its moments of inertia is:

If we treat the person as a point mass, then the total moment of inertia of the system about the center of the disk when the person stands on the rim of the disk:

2) Similarly, he total moment of inertia of the system about the center of the disk when the person stands at the final location 2/3 of the way toward the center of the disk (1/3 of the radius from the center):

3) Since there's no external force, we can apply the law of momentum conservation to calculate the angular velocity at R/3 from the center:



4)Kinetic energy before:

Kinetic energy after:

So the change in kinetic energy is: 2374 - 1430 = 944 J
5) 
6) If the person now walks back to the rim of the disk, then his final angular speed would be back to the original, which is 1.8 rad/s due to conservation of angular momentum.