# Heat (Aluminum vs Steel)

1. Nov 28, 2004

### Bcisewski

Based on contraction and expansion due to heat and cold, have I assumed the correct answer with a sample equation to the question below.

For the highest accuracy, would you choose an aluminum or a steel tape rule for year-round outdoor use? Why?

“Aluminum” – The heat “Q” that must be supplied or removed to change the temperature of the given substance of “m” by the amount of “T” is less with steel. So if the “Q” reached capacity for aluminum to change, the change would occur at approximately twice the amount of steel by using the formula:
Q=cm(delta)T with both tape measure of equal mass
Aluminum Q=(9.00x10^2 Alumin)(1 mass)(45 Temp)=40500 Joules "Change would occur at 40500 Joules"
Steel Q=(452)(1)(45)=20340 Joules "Change would occur at 20340 Joules"

2. Nov 28, 2004

### Tide

I don't think it's simply a matter of heating and cooling. I'd worry more about thermal expansion. Check out and compare the thermal expansion coefficients for the two materials. You might want to reconsider your answer!