The energy required to heat a substance is related by the formula:
Q = mCpΔT ; where Q is the energy, m is the mass of the substance, Cp is the specific heat capacity and ΔT is the change in temperature.
2000 = (4)(Cp)(5)
Cp = 100 Joules / g °C
At the top, the roller coaster has a very large amount of potential energy. This amount of potential energy is present because the roller coaster is at a elevated place with respect to the ground. While the roller coaster goes down some of the potential energy is lost depending on the change in height and is converted to other energy. As the roller coaster is losing the potential energy, it gains some kinetic energy since this type of energy is dependent on the speed of the object moving and the mass. Therefore the answer i believe is where potential energy is converted to kinetic energy.
The term used for the total radiation that is reflected by a surface is albedo. It is the percent of solar energy that is being reflected from our Earth back into the space. It is a dimensionless value since it is a percentage and ranges from a value of zero (corresponds to a perfect black body where it absorbs all of the radiation) to one (corresponds to a white body where all radiation is being reflected). This term is very useful in astronomy, climatology and environmental management. The average albedo of Earth is found to range from 30 percent to 35 percent due to the clouds present in the atmosphere.
STEP ONE:
Let you and your friend stand as far away as possible from a large reflecting wall and clap your hands rapidly at a regular rate.
STEP TWO:
Adjust this rate until each clap just coincides with the return of an echo of its predecessor, or until clap and echo are heard as equally spaced.
STEP THREE:
Use a stopwatch to find the time between claps, t. Make a rough measurement of distance to the wall, s. Thus the speed of sound, v = 2s/t