Answer:
1. Gravitational potential energy is the energy that an object has because of its height and is equal to the object's mass multiplied by its height multiplied by the gravitational constant (PE = mgh). Gravitational potential energy is greatest at the highest point of a roller coaster and least at the lowest point.
2. Kinetic energy is energy an object has because of its motion and is equal to one-half multiplied by the mass of an object multiplied by its velocity squared (KE = 1/2 mv2). Kinetic energy is greatest at the lowest point of a roller coaster and least at the highest point.
3.Initially, before the big bang, the universe-ball was at rest. Now, after the big bang, it is falling: light and matter exist, and they are moving. And yet, because of the negative energy built into the gravity field created by these particles, the total energy of the universe remains zero.
4. When the temperature of an object increases, the average kinetic energy of its particles increases. When the average kinetic energy of its particles increases, the object's thermal energy increases. Therefore, the thermal energy of an object increases as its temperature increases.
5. When the skater is dropped onto the ramp from above, the potential energy decreases and the kinetic energy increases. Every time the skater bounces from the impact, thermal energy is gained, and both potential and kinetic energy are lost.
