8.13

[Connie2I]

For problem 8.13, why is the value of q = 947 kJ negative? I had thought it was positive because the question said that heat was absorbed.

[Lisa Tang 1C]

The value of q is negative because the problem states that "the cooling system that surrounds the cylinder absorbs 947 kJ as heat." I think this means that the surroundings absorb the heat, and the actual cylinder itself releases it.

[Julie Steklof 1A]

Yes, the surroundings (the cooling system) gain 947 kJ as heat meaning that the system must lose 947 kJ.

[Charles Ang 1E]

In this question the q(of the cylinder) = -w(of the fuel). Which is why when calculating the work of the fuel, the value of q is negative.