Understanding Heat and Work - High School Physics
Card 0 of 4
of heat is added to a gas in a closed container. If the lid to the container is lifted 
with 
of force, what is the net energy added to the system?
The formula for the net energy added to a system is;
The change in energy equals the heat energy minus the work done.
We don't know the work, but we can solve for it using the work equation:
We are given both the force and the distance, allowing us to calculate the work.
Now that we know both the work done and the heat added, we can solve for the final energy of the system.
The formula for the net energy added to a system is;
The change in energy equals the heat energy minus the work done.
We don't know the work, but we can solve for it using the work equation:
We are given both the force and the distance, allowing us to calculate the work.
Now that we know both the work done and the heat added, we can solve for the final energy of the system.
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A certain amount of heat energy is added to a closed system. A few moments later, a scientist observes that the total increase in energy is LESS than that heat energy added to the system. Which could be a valid explanation for this conclusion?
A certain amount of heat energy is added to a closed system. A few moments later, a scientist observes that the total increase in energy is LESS than that heat energy added to the system. Which could be a valid explanation for this conclusion?
The most likely explanation is that work is done by the system.
The formula for change in energy shows that the net change in energy is equal to the increase in heat energy minus the work done:
Since 
, there must have been work done by the system.
The most likely explanation is that work is done by the system.
The formula for change in energy shows that the net change in energy is equal to the increase in heat energy minus the work done:
Since
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A bathtub and a coffee cup both contain water at 
. Which of the following is true?
A bathtub and a coffee cup both contain water at
Heat is a form of energy, while temperature is a measure of the average kinetic energy of the molecules present in a system. Since both systems are measure to be at 
, their average kinetic energies are the same. The cup and the bathtub have the same temperature; however, since the bathtub contains more water, it contains more molecules. Temperature is the measure of heat energy per molecule. A greater number of molecules at the same temperature is indicative of more heat energy than fewer molecules at that temperature. Since the bathtub has more molecules, it has more heat energy even though the two systems have the same temperature.
Heat is a form of energy, while temperature is a measure of the average kinetic energy of the molecules present in a system. Since both systems are measure to be at
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In order for heat transfer to occur, which of the following must be present?
In order for heat transfer to occur, which of the following must be present?
A temperature gradient is always needed for heat transfer to occur. The temperature difference is what drives a flow of heat, as heat will always travel from an area of higher temperature to an area of lower temperature. This can occur between two materials, or within a single material. For example, if an iron pot is placed on a stovetop, the entire metal pot will become hot even though only the bottom is in contact with the heat source. This is because the heat transfers through the metal, from the high heat at the bottom to the lower heat at the top.
A temperature gradient is always needed for heat transfer to occur. The temperature difference is what drives a flow of heat, as heat will always travel from an area of higher temperature to an area of lower temperature. This can occur between two materials, or within a single material. For example, if an iron pot is placed on a stovetop, the entire metal pot will become hot even though only the bottom is in contact with the heat source. This is because the heat transfers through the metal, from the high heat at the bottom to the lower heat at the top.
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