1. Most PE, because PE is directly proportional to distance (height)
Height: 100 meters
Speed: 0 mph
2. Most KE, because KE is directly proportional to speed
Height: 10 meters
Speed: 40 mph
3. Most TE, average KE
Height: 10 meters
Speed: 40 mph
4. The skater gains thermal energy as she goes down the slope, because the speed of the skater increases, so it increases the total kinetic energy of the particles, and makes them vibrate faster, resulting in a higher temperature.
There are two different processes here:
1) we must add heat in order to bring the temperature of the water from
to
(the temperature at which the water evaporates)
2) other heat must be added to make the water evaporates
1) The heat needed for process 1) is
where
is the water mass
is the water specific heat
is the variation of temperature of the water
If we plug the numbers into the equation, we find
2) The heat needed for process 2) is
where
is the water mass
is the latent heat of evaporation of water
If we plug the numbers into the equation, we find
So, the total heat needed for the whole process is
Answer:
Solar water heaters are devices that use energy from the sun to heat water. ... This metal surface, placed in contact with the water, will heat the water. Black-painted surfaces that receive the sun's heat become hotter than surfaces of any other color. The black metal plate is called a collector.