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What is the change in internal energy (in J) of a system that absorbs 0.464 kJ of heat from its surroundings and has 0.630 kcal of work done on it?

Answer 1

Charlotte Aaron

I found an increase of #3100J#

Have a look:

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Answer 2

William Audy

To calculate the change in internal energy (ΔU) of the system, you can use the first law of thermodynamics, which states that the change in internal energy (ΔU) of a system is equal to the heat (Q) added to the system minus the work (W) done by the system on its surroundings.

Given:
Heat absorbed (Q) = 0.464 kJ
Work done on the system (W) = 0.630 kcal

First, convert the work done on the system from kilocalories (kcal) to kilojoules (kJ):
1 kcal = 4.184 kJ
So, 0.630 kcal = 0.630 * 4.184 kJ = 2.637 kJ

Now, use the first law of thermodynamics to calculate the change in internal energy:
ΔU = Q - W
ΔU = 0.464 kJ - 2.637 kJ
ΔU = -2.173 kJ

Therefore, the change in internal energy of the system is -2.173 kJ.

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.