Question

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?

Answer 1

The work done by fuel on the piston in the cylinder is 3799.6 kJ, calculated using the first law of thermodynamics with the given internal energy change and heat absorbed.

Step-by-step explanation:

To determine the amount of work done by the fuel on the piston, we use the first law of thermodynamics which states that the change in internal energy (ΔU) is equal to the heat added to the system (Q) minus the work done by the system (W). In this case, the combustion of the fuel results in a change in internal energy of –2836 kJ. The cylinder absorbs 963.6 kJ of heat. Therefore, we can write the first law as:

ΔU = Q - W

Substituting the given values, we have:

–2836 kJ = 963.6 kJ - W

To solve for W, we rearrange this equation:

W = 963.6 kJ + 2836 kJ

W = 3799.6 kJ

The combustion of fuel can do 3799.6 kJ of work on the piston.

Answer 2

Step-by-step explanation:

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 .