Question

Helium gas expands in a piston-cylinder in a polytropic process with n=1.67. Is the work positive, negative or zero?

Answer 1

work will be positive when it is under polytropic expansion process

Step-by-step explanation:

It states a polytropic process with n equal to 1.67. there is a polytropic expansion that mean work is positive and if it was polytropic compression then it would be negative

`PV^n = const`

`P_1V_1 = P_2V_2`

Also work during the process of polytropic is given as

`W_(1-2) =(P_1V_1 -P_2V_2)/(n-1)`

the work will be positive when it is under the polytropic expansion process