The AMOUNT of energy the ball has doesn't change. It's 294 joules in Darwin's hand, and it's still 294 joules when the ball hits the ground. It's all PE before he let's it go, and it steadily changes from PE to KE all the way down.
It BEGINS to turn into KE immediately, when Darwin lets go of the ball, and it starts to fall.
More and more PE turns into KE as the ball falls, all the way down.
When the ball hits the ground, it has no more PE left. All of its mechanical energy is then KE.
It would be D I believe! Depending on the angle of the mirror and distance positioned!
Answer:

Explanation:
<u>Conservation of Momentum
</u>
The total momentum of a system of two particles is

Where m1,m2,v1, and v2 are the respective masses and velocities of the particles at a given time. Then, the two particles collide and change their velocities to v1' and v2'. The final momentum is now

The momentum is conserved if no external forces are acting on the system, thus

Let's put some numbers in the problem and say



120=120
It means that when the particles collide, the first mass returns at 6 m/s and the second continues in the same direction at 28 m/s
Answer:
During the segments B - C and D - E, the car stopped since the y axis is the distance and the distance stayed the same in between those segments.
For a simpler answer, the flat horizontal lines on the graph are the times when the car was stopped.
Assuming that the angle is the same for both ropes, then D. is the answer. You have to consider also if the ropes are close together or far apart and if the force to move the object is in line with the ropes or perpendicular to them.
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