Find the heat that flows into or out of the system

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SUMMARY

The discussion focuses on calculating heat transfer in a thermodynamic system undergoing expansion. The system expands by 0.75 m³ at a constant pressure of 125 kPa. For an increase in internal energy of 65 J, the heat transfer (Q) is calculated as 0.15878 kJ. Conversely, for a decrease in internal energy of 1850 J, the heat transfer is 1.77 kJ. The correct formula for work done (W) in this context is W = PΔV, not W = P(ΔU).

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Homework Statement


A system expands by 0.75 m^3 at a constant pressure of 125 kPa. Find the heat that flows into or out of the system if its internal energy
a. Increases by 65J
b. Decreases by 1850 J
give answer kJ


Homework Equations





The Attempt at a Solution


P=125 kPA
delta U=Q-W
W=P(delta U)
so i plug in the numbers
W=(125kPa)(0.75m^3)=93.75

Part a)
delta U=65kPA

65=Q-93.75
Q= 158.75 J= .15878 kJ

Part B)
1850= Q-93.75
Q= 1756.25J=1.77kJ

And the answer is wrong, can someone help me please
 
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no i meant W=P(delta V)
I just typed in the wrong thing
sorry for the mistake
so do you know what i should do
 

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