Because chemical changes result in different substances, they often cannot be undone. Some chemical changes can be reversed, but only by other chemical changes.
Answer:
he kinetic energy increases on the descent, being maximum at the lowest point of the trajectory.
Explanation:
In these semicircular sections the skaters slide from one side to the other, in the downward path their kinetic energy increases and their potential energy decreases; When it leaves the ramp and is in the air, the kinetic energy decreases rapidly, up to the point of maximum height where the kinetic energy is zero.
Consequently, the kinetic energy increases on the descent, being maximum at the lowest point of the trajectory.
Try this solution (if it is possible, check it in other sources):
1. for m_Tarzan=75kg., initial_height=4m., end_height=0 m. and g=10 N/kg. Energy is:

2. The same value of Energy is applied for m_Tarzan+Jane=75+50=125 kg.:

3. According to the formula of the Speed:
Speed=sqrt(6000/125)=sqrt(48)=4sqrt(3)≈4*1.71=6.84 (m/s)
Answer: 6.84 (m. per sec.)
From areas of high potential to low potential. That is, high voltage to low voltage.
Answer:
it is zero because the electric gap is zero within the material
Explanation:
In a metal you have many free electrons, and fixed charges formed by nuclei and electrons that are not free; therefore the charge carriers are the free electrons, these have the same negative charge and due to the lectrostatic force they repel each other as far as possible without leaving the material, this implies that at two points there must be the same potential because otherwise there would be a net Caesarian force accumulating charge in a part that would be eliminated by the Coulomb force.
With this we can review the statements the strap is: it is zero because the electric gap is zero within the material