Comparing thermo dynamic processes

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The discussion focuses on calculating the work done on an ideal gas during different thermodynamic processes: isothermal, adiabatic, and isobaric. For isothermal compression, the work done is derived from the ideal gas law, while for adiabatic processes, the relationship involves changes in internal energy and temperature. The participant suggests that the absolute value of the change in internal energy is greatest in isobaric processes due to constant pressure, while it is least in isothermal processes, where temperature remains constant and thus internal energy does not change. There is confusion regarding how compression occurs in an isobaric process while maintaining constant pressure. Overall, the thread explores the relationships between work, pressure, volume, and internal energy in thermodynamic processes.
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Homework Statement



in a cylinder, 1.2 mol of an ideal gas, gamma = 1.67 initially at 3.60 x10^5 pa
and 300k, is compressed until the volume is halved.

I need help with 1) c
and
2)

Compute work done on the gas if the compression is:

1)

a) isothermal
b) adiabatic
c) isobaric

2) in which case is the absolue value of the change in internal energy of the gas the greatest? least?

Homework Equations



I think i have a and b worked out.

The Attempt at a Solution



for c) would this be the correct approach?

is this part correct?

V1 = ?
V2 = 1/2V1

w = p(V2 - V1)
w = p(1/2v - v)

pv = nrt

w = -1/2nrt?

2) greatest is isobaric because?
least is isothermal because delta u =0 constant temp and temp is related to change in internal energy.
 
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How can the gas get compressed if the process is isobaric? What other property must change?
 
the volume is being compressed. But, th pressure remains constant so the area of work is less than the other 2 processes? Adiabatic is the most?
 
Thread 'Variable mass system : water sprayed into a moving container'

Thread 'Variable mass system : water sprayed into a moving container'

Starting with the mass considerations #m(t)# is mass of water #M_{c}# mass of container and #M(t)# mass of total system $$M(t) = M_{C} + m(t)$$ $$\Rightarrow \frac{dM(t)}{dt} = \frac{dm(t)}{dt}$$ $$P_i = Mv + u \, dm$$ $$P_f = (M + dm)(v + dv)$$ $$\Delta P = M \, dv + (v - u) \, dm$$ $$F = \frac{dP}{dt} = M \frac{dv}{dt} + (v - u) \frac{dm}{dt}$$ $$F = u \frac{dm}{dt} = \rho A u^2$$ from conservation of momentum , the cannon recoils with the same force which it applies. $$\quad \frac{dm}{dt}...
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