Answer:
The cup of water has a higher average kinetic energy
Lake Michigan has a higher total kinetic energy
Explanation:
Kinetic energy is the energy an object possesses due to its motion. It is commonly called energy in motion.
The average kinetic energy of the molecules in a body is the mean kinetic energy of the individual molecules. In the case in question, the two bodies are "a cup of water" and "Lake Michigan". Heat increases the kinetic energy of a substance. since the cup of water is boiling, the individual water molecules in the cup have a higher kinetic energy than the individual molecules each of the water molecules in lake Michigan whose temperature is at environmental temperature.
Using Hypothetical values, Let's say the cup of water contains 10 molecules of boiling water which is at a temperature of 100°C, and the water in lake Michigan has 10000 molecules of water at temperature of say 25°C. since kinetic energy is directly proportional to temperature rise, it will be correct to say let the Kinetic energy of each individual molecule in the cup of boiling water be 100 Joules, while the kinetic energy of the individual molecules of water in Lake Michigan be 25 Joules. The average kinetic energy is the sum of the individual kinetic energy of the water molecules divided by the total number of water molecules in the body. Hence the average kinetic energy for the water molecules in the cup will be 100 Joules, while that of Lake Michigan will be 25 Joules, four times lower than the average kinetic energy of the water molecules in the cup, even though the total number of molecules in Lake Michigan is 1000 times that in the cup.
On the other hand, the total kinetic energy of the water molecules in each body is the sum of all the individual kinetic energies of the water molecules. So, using our hypothetical value, the total kinetic energy of Lake Michigan will be 25000 Joules, while that of the cup of water is 1000 Joules, making the total kinetic energy in Lake Michigan higher than that of the cup by 25.
In conclusion it can be said that size affects total kinetic energy, while size do not have significant effect on average kinetic energy.
