Work Flashcards
What is work?
Mechanical way of transfer of energy
Formula of work for gases?
W= -Pext ∆V ( when pressure is constant)
What happens during expansion?
During expansion, work is done BY the gas
So
W= -ve
∆V= +ve
What happens during compression?
Work is done ON the gas
So
W= +ve
∆V= -ve
1atml = ? J
1atml=101.3 J
Formula for area of trapezoid?
Area of trapezium = 1/2(Sum of || sides)×height
Formula for work done for a curve ( P-V graph)?
W= Area under P-V curve
Formula of work done when P is variable?
W= –∫PdV ( limit— V1 to V2)
What is the work done by a straight line parallel to P axis?
Zero
Because area for a straight line is zero
work done by cyclic process ≠ ?
Zero
Work ≠ state function
Work = Path function
Work done by cyclic process formula?
W= Area of cycle
If
Clockwise — -ve
A.C.W. — +ve
What is the work done by Isochoric process?
W=0
( Isochoric= constant volume)
W=-Pext ∆V
Work done by isobaric expansion?
W= -Pext ∆ V
( Isobaric= constant pressure)
Boyle’s law?
At constant temperature
P ∝ 1/V
P1V1 = P2V2
Formula for work done by Reversible Isothermal expansion?
W= – 2.303 nRT ln (V2/V1)
