OUNT OF HEAT ABSORBED AND WORK DONE IN A PV DIAGRAM?

Click For Summary
SUMMARY

The discussion focuses on calculating the work done and heat absorbed by a dilute gas during a process represented on a PV diagram. The initial state of the gas is at 1.00 atm and 14.0 L, while the final state is at 2.00 atm and 78.0 L. The correct method to find the work done involves calculating the area under the PV curve down to P=0, rather than assuming it forms a triangle. Additionally, the relationship between work, heat flow, and change in internal energy is emphasized, highlighting the need to determine the change in temperature to find the heat absorbed.

PREREQUISITES
  • Understanding of PV diagrams and gas laws
  • Knowledge of thermodynamic concepts such as work and heat transfer
  • Familiarity with unit conversions, particularly from liters to cubic meters
  • Basic principles of internal energy and its relation to heat and work
NEXT STEPS
  • Calculate work done using the area under the PV curve for various processes
  • Study the first law of thermodynamics and its applications
  • Learn about the ideal gas law and its implications in thermodynamic processes
  • Explore temperature changes in gases and their effect on internal energy
USEFUL FOR

Students studying thermodynamics, physics enthusiasts, and anyone involved in understanding gas behavior in thermodynamic processes.

paradiselost5
Messages
1
Reaction score
0

Homework Statement



One mole of a dilute gas initially has a pressure equal to 1.00 atm, and a volume equal to 14.0 L. As the gas is slowly heated, the plot of its state on a PV diagram moves in a straight line to the final state. The gas now has a pressure equal to 2.00 atm, and a volume equal to 78.0 L.

(a) Find the work done by the gas.


(b) Find the heat absorbed by the gas.

Homework Equations





The Attempt at a Solution


I took the area under the PV curve which is a triangle... 64/2*101.325
 
Physics news on Phys.org
paradiselost5 said:


The Attempt at a Solution


I took the area under the PV curve which is a triangle... 64/2*101.325

Watch out: It is not a triangle. The work done by the gas is the area under the PV curve down to P=0.

ehild
 
In addition to what ehild points out, watch the units for volume. If you are using MKS units you have to convert litres to _________.

What is the relationship between work done, heat flow and change in internal energy? To find the heat flow, what other quantity do you have to find? (hint: what is the change in temperature?).

AM
 

Similar threads

  • · Replies 6 ·
Replies
6
Views
2K
Replies
11
Views
5K
Replies
11
Views
2K
Replies
5
Views
3K
  • · Replies 4 ·
Replies
4
Views
2K
  • · Replies 9 ·
Replies
9
Views
2K
  • · Replies 7 ·
Replies
7
Views
3K
Replies
3
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 2 ·
Replies
2
Views
3K