“A hot object has greater average kinetic energy but may not have greater total kinetic energy “
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A cold bullet shot at your hand is going to damage your hand (more energy) than a sizzling hot bullet sitting on your palm.
I think the key is “greater average RELATIVE kinetic energy”. It’s kind of implicit because temperature has to do with how much relative motion is happening within the particles of an object. It doesn’t mean it has more total kinetic energy because the whole object can also be moving all together with a lot more kinetic energy.
The sentence as written can be mathematically confusing if you miss the implicit “relative”.
A cold bullet shot at your hand is going to damage your hand (more energy) than a sizzling hot bullet sitting on your palm.
I think the key is “greater average RELATIVE kinetic energy”. It’s kind of implicit because temperature has to do with how much relative motion is happening within the particles of an object. It doesn’t mean it has more total kinetic energy because the whole object can also be moving all together with a lot more kinetic energy.
The sentence as written can be mathematically confusing if you miss the implicit “relative”.
A lot of people in here are talking about bulk movement vs temperature, but the question as posed makes me think that you might be looking for an explanation of thermal energy vs temperature. So, what’s the thermal energy of an object? It’s the total amount of energy that contributes to temperature. To illustrate the difference, lets imagine 2 rocks. They’re made of the same stuff, but one is way bigger than the other. Now we do an experiment: we place each rock separately in highly insulated box and see what happens to the temperature of the system after a period of hours. After each trial, we reset the box to a standardized temperature. Whenever we do this, so long as the small rock is not MUCH hotter than the large rock, we will find that the large rock alters the temperature of the box more than the small rock does. This is because it takes more total energy to heat the large rock to the same temperature as the small rock.
A lot of people in here are talking about bulk movement vs temperature, but the question as posed makes me think that you might be looking for an explanation of thermal energy vs temperature. So, what’s the thermal energy of an object? It’s the total amount of energy that contributes to temperature. To illustrate the difference, lets imagine 2 rocks. They’re made of the same stuff, but one is way bigger than the other. Now we do an experiment: we place each rock separately in highly insulated box and see what happens to the temperature of the system after a period of hours. After each trial, we reset the box to a standardized temperature. Whenever we do this, so long as the small rock is not MUCH hotter than the large rock, we will find that the large rock alters the temperature of the box more than the small rock does. This is because it takes more total energy to heat the large rock to the same temperature as the small rock.
A lot of people in here are talking about bulk movement vs temperature, but the question as posed makes me think that you might be looking for an explanation of thermal energy vs temperature. So, what’s the thermal energy of an object? It’s the total amount of energy that contributes to temperature. To illustrate the difference, lets imagine 2 rocks. They’re made of the same stuff, but one is way bigger than the other. Now we do an experiment: we place each rock separately in highly insulated box and see what happens to the temperature of the system after a period of hours. After each trial, we reset the box to a standardized temperature. Whenever we do this, so long as the small rock is not MUCH hotter than the large rock, we will find that the large rock alters the temperature of the box more than the small rock does. This is because it takes more total energy to heat the large rock to the same temperature as the small rock.
Analogy: think of the country of Richovia, which has two people. One has 4 million dollars, the other has 6 million.
Next door is Pooristan, with fifty million people. Each of them has one dollar.
Richovia’s average money per citizen is 5 million, and their total is 10 million.
Pooristan’s average per citizen is $1…but their total is 50 million. Lower average, higher total.
In the same way, you could have a small high-average-energy thing (match flame) and a big low-average-energy thing (old boulder) and the boulder could have a higher total energy, even though its average is way lower.
Analogy: think of the country of Richovia, which has two people. One has 4 million dollars, the other has 6 million.
Next door is Pooristan, with fifty million people. Each of them has one dollar.
Richovia’s average money per citizen is 5 million, and their total is 10 million.
Pooristan’s average per citizen is $1…but their total is 50 million. Lower average, higher total.
In the same way, you could have a small high-average-energy thing (match flame) and a big low-average-energy thing (old boulder) and the boulder could have a higher total energy, even though its average is way lower.
Analogy: think of the country of Richovia, which has two people. One has 4 million dollars, the other has 6 million.
Next door is Pooristan, with fifty million people. Each of them has one dollar.
Richovia’s average money per citizen is 5 million, and their total is 10 million.
Pooristan’s average per citizen is $1…but their total is 50 million. Lower average, higher total.
In the same way, you could have a small high-average-energy thing (match flame) and a big low-average-energy thing (old boulder) and the boulder could have a higher total energy, even though its average is way lower.
The water in your teapot is way hotter than the water in your radiators. The average temperature of the pot is so high (average kinetic energy) yet it’s virtually useless to heat your home alone (total kinetic energy).
The water in your teapot is way hotter than the water in your radiators. The average temperature of the pot is so high (average kinetic energy) yet it’s virtually useless to heat your home alone (total kinetic energy).
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