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Chapter 21: Q. 12 (page 594)

A gas following the pVtrajectory of FIGURE EX21.12does 60Jof work per cycle. What is pmax?



Short Answer

Expert verified

The value ofpmax=300kPa.

Step by step solution

01

Step: 1 Definition of pmax:

In case of varying pressure and volume , work done by a gas can be calculated by calculating the area of P-V curve . In case of triangle area of triangle can be calculated by the following formula .

A=12×b×h

A is area , b is length of base and h is height of triangle.

02

Step: 2 Finding the value of pmax:

The area enclosed by the graph is equal to the work done by the gas. That example, if we allow the maximum pressure value to be in kPa, as the figure is a triangle, we have

Wout=pmax−100⋅103⋅(800−200)⋅10−62

pmax−100=2Wout6⋅10−1⇒pmax=2Wout6⋅10−1+100kPa.

03

Step: 3 Calculation:

We can substitute the value and calculate as follows.

pmax=2×600.6+100pmax=300kPa.

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Most popular questions from this chapter

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