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100J of work is done by the system and internal energy changes by +76J. How much heat was transferred?

100J of work is done by the system and internal energy changes by +76J. How much heat-example-1
User Dgnorton
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1 Answer

6 votes

Answer:

24 J taken out of the system

Step-by-step explanation:

Since work is done on the system, it should be negative. So the correct equation is:

ΔU = Q - W

where ΔU is the change in internal energy, Q is the heat added to the system, and W is the work done on the system.

In this case, we know that the internal energy changes by +76 J and 100 J of work is done on the system (with a negative sign). So we can substitute these values into the formula and solve for Q:

ΔU = Q - W

76 J = Q - (-100 J)

76 J = Q + 100 J

Q = 76 J - 100 J

Q = -24 J

Therefore, the amount of heat transferred to the system is -24 J. This negative value means that heat is leaving the system rather than entering it.

User Bonfo
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