Work done through linear expansion

AI Thread Summary
To calculate the work done by the aluminum flagpole during linear expansion, the formula w = PΔV is used, where P is the pressure and ΔV is the change in volume. The initial volume at 10°C is determined using the mass and density of aluminum, resulting in approximately 2.963 m³. The flagpole expands by 0.024 m due to a temperature increase from 10°C to 20°C, which affects its volume. The coefficient of volume expansion, related to the linear expansion coefficient, is necessary for finding the final volume at 20°C. The expected answer for the work done is 213 J, highlighting the importance of understanding volume expansion in this context.
LadyMario
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An 8000kg aluminum flagpole 100m long is heated by the sun from a temperature of 10°C to 20°C. Find the work done (in J) by the aluminum if the linear expansion coefficient is 24*10-6 /°C. (The density of aluminum is 2.7*103 kg/m3 and 1 atm = 1.0*105 N/m2)

I know w=PΔV, and I know V at 10°C = mass/density= 8000/2.7*103 = 2.963m3

I know how much longer the flagpole grows: ΔL=αLΔT = 24*10-6(100)(20-10)=0.024m

But how does the volume at 20°C relate to the growth of the flagpole through linear expansion?

The answer is suppsoed to be 213 J.
 
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Do you know the formula for volume expansion? The coefficient of volume expansion has a simple relation to the coefficient of linear expansion.
 
TSny said:
Do you know the formula for volume expansion? The coefficient of volume expansion has a simple relation to the coefficient of linear expansion.

Yea I found it in the textbook. We were never taught it in class, so I was trying to find another way to do it, but oh well :P
 
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