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A piston absorbs 42 J of heat from its surroundings while being compressed from 0.0007 m3 to 0.0002 m3 at a constant pressure of 1.0 × 105 Pa. What are the correct values for heat and work for the piston?

A piston absorbs 42 J of heat from its surroundings while being compressed from 0.0007 m-example-1
User Alie
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2 Answers

4 votes

Final answer:

The correct values for heat and work for the piston are 42 J and -5.0 × 10^4 J, respectively.

Step-by-step explanation:

In this question, we are given the initial volume (V1 = 0.0007 m³), the final volume (V2 = 0.0002 m³), and the constant pressure (P = 1.0 × 10^5 Pa). We need to find the heat (Q) and work (W) done by the piston.

The work done by the piston is given by the equation:

W = PΔV

where ΔV = V2 - V1 is the change in volume.

The heat absorbed by the piston is given by the equation:

Q = nCΔT

where ΔT is the change in temperature and C is the specific heat capacity of the gas.

Since the pressure is constant, the work done can be calculated using the equation:

W = PΔV

Substituting the given values, we have:

W = (1.0 × 10^5 Pa) * (0.0002 m³ - 0.0007 m³)

Calculating the work:

W = -5.0 × 10^4 J

Since the process is carried out at constant pressure, the heat absorbed can be calculated using the equation:

Q = nCΔT

Since the gas is ideal, we can use the equation:

nCΔT = CΔT = Q

Substituting the given values, we have:

Q = CΔT = 42 J

Therefore, the correct values for heat (Q) and work (W) for the piston are 42 J and -5.0 × 10^4 J, respectively.

User Alexandre Thenorio
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4.8k points
4 votes

Answer:

D

Step-by-step explanation:

W = P∆V

Use the above equation and substitute, thanks

User Bloke
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5.2k points