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Enoch
Dec12-04, 02:49 PM
Gas in a container expands at a constant pressure of 95 atmospheres. Find the work done by the gas if the initial volume is 5 L and the final volume is 10 L. Answer in units of Joules.

I thought this problem was straight-forward, but I missed it.

I converted 95 atmospheres into Pascals.

95 X 1.013e5 PA = 9623500

I then converted L into meters ^3.

Vi = 0.5 m^3
Vf = 1 m^3

With the units converted, I used the equation W = P(Vf - Vi) and got the answer 4811750 Joules. The answer is incorrect, or so I believe.

Where did I go wrong?

dextercioby
Dec12-04, 02:54 PM
Gas in a container expands at a constant pressure of 95 atmospheres. Find the work done by the gas if the initial volume is 5 L and the final volume is 10 L. Answer in units of Joules.

I thought this problem was straight-forward, but I missed it.

I converted 95 atmospheres into Pascals.

95 X 1.013e5 PA = 9623500

I then converted L into meters ^3.

Vi = 0.5 m^3
Vf = 1 m^3

With the units converted, I used the equation W = P(Vf - Vi) and got the answer 4811750 Joules. The answer is incorrect, or so I believe.

Where did I go wrong?

There's no problem with the conversion of the pressure's units to SI,but remember that
1m^3=1000L

Enoch
Dec12-04, 03:05 PM
There's no problem with the conversion of the pressure's units to SI,but remember that
1m^3=1000L

Thanks alot!