Work done by a gas

—> Work done : energy transferred, measured in Joules (J)

—> to move the rod, gas is used to move a piston.
—> the energy transferred to the piston by the gas is known as ‘work done’
—> is equal to the force times distance moved in the direction of the force

—> if the position of the piston is defined as ‘x’ then the distance moved by the piston is

• △x = x2 - x1

—> and so the work done by the gas is

• W = F x △x

—> as the height of the piston changed by △x, the volume changes too.

—> work done by an expanding gas is equal to the pressure times change in volume

• W = p△V

(△ = change in
x = distance
W = work done
P = pressure)

W = F△x

P = F/A so F= P x A

(X x A = V)

W = P x A x △x

W = P△V