The mechanical energy of the roller coaster is sum of kinetic energy K and gravitational potential energy U:

where

is the kinetic energy

is the gravitational potential energy
Since the ride is frictionless, the total mechanical energy E is conserved during the ride. Therefore, at the top of the hill, the potential energy is maximum, because h (the height) is maximum, and this means the kinetic energy is minimum (because the sum of K and U is constant), so the velocity will be minimum. Viceversa, at the bottom of the hill, the potential energy will be minimum (because h is minimum), so the kinetic energy K will be maximum, and the velocity v of the roller coaster will be maximum.
Answer:
P₂ = 2 P₁
we conclude that in the second time the power used is double that in the first rise
Explanation:
In this exercise we are asked the power to climb the stairs, if we assume that we go up with constant speed, we use an energy equal to the potential energy due to the difference in height of the stairs, as this height is constant the potential energy does not change and therefore therefore the energy used by us does not change either.
Now we can analyze the required power,
P = W / t
From the analysis of the previous paragraph the work is equal to the energy used, according to the work energy theorem,
therefore the first time the power is
P₁ = E / 10
P₁ = 0.1 E
for the second time the power is
P₂ = E / 5
P₂ = 0.2 E
we see that the power in the second case is
P₂ = 2 P₁
Therefore, we conclude that in the second time the power used is double that in the first rise.
Answer:A skier could benefit from a sports-specific training program because it could help them become better at skiing. ... Other activities such as squats and lunges will also improve skiing skills since it builds up lower body strength which is necessary to ski tough terrain.
Explanation:
Scientists believe that light is made of streams of particles because light exhibits the particle nature. This can be explained on the basis of photoelectric effect observed when light is made to fall on the surface of a metal. when light falls on the surface of a metal, it makes the electron to eject out. This is possible only when light consists of small particle called photons. hence the scientists believe that light is made of streams of particles.