Air Cylinder

- Filed under Business and Industrial

Air Cylinder

Consider a mixture of air and gasoline vapor in a cylinder with a piston. The original volume is 60. cm3. If t

Consider a mixture of air and gasoline vapor in a cylinder with a piston. The original volume is 60. cm3. If the combustion of this mixture releases 1379. J of energy, to what volume will the gases expand against a constant pressure of 650. torr if all the energy of combustion is converted into work to push back the piston?

The work done on the environment by the volume expansion of a system against a constant resisting pressure is given by:

w = P * delta-V

where P is the pressure and delta-V is the final volume minus the initial volume.

In this question you are told that the 1379 J of energy is converted to mechanical (expansion) work.

This means that

1379 J = 650 torr * (v_final - 60 cm^3)

It will make things easier if we convert all the units to mks units in this equation.

655 torr = 8.67*10^4 Pa

60 cm^3 = 6.00*10^-5 m^3

Then

1379 J = 8.67*10^4 Pa * (v_final - 6.00*10^-5 m^3)

v_final = (1379 J)/(8.67*10^4 Pa) + 6.00*10^-5 m^3

v_final = 1.60*10^-2 m^3 = 1.60*10^4 cm^3

 »  admin