The combustion of fuel in a piston cylinder causes an internal energy change of - 2836 kJ. The components surrounding the cylinder absorb 963.6 kJ of heat. How much work can be done by the fuel on the piston in the cylinder?

From first law of thermodynamics

Q = ΔE + W

Q is heat added, ΔE is increase in internal energy and W is work done.

Here Q = - 963.6 kJ, - ve sign because head is absorbed

ΔE - 2836 kJ, negative sign given (gas cooled)

Putting these values in the equation above

- 963.6 = - 2836 + W

W = 2836 - 963.6 kJ

= 1872.4 kJ.