- #1

Logan McEntire

- 4

- 0

## Homework Statement

The tires on a bicycle require an air pressure of 80 psig. When isothermally pumped up the bicycle tires, the volume of the air (that was originally in the atmosphere) is reduced by a factor of 5.7. Please determine the work that must be done on each lbm of air that is pumped into the tires. Please report your answer in lbf-ft/lbm.

.

## Homework Equations

W=nRT*ln(V2/V1)

Pv=nRT

## The Attempt at a Solution

My attempt might be very wrong, but this is what i tried.

I simplified Pv=nRT to T=PV/nR

Plugged that into W=nRT*ln(V2/V1)

W=PV*ln(V2/V1)

I know the standard pressure (14.7psi) and the pressure inside the tire (80psig+14.7psi=94.7psi), but I don't know the volume of to plug in for the V.