# Linear expansion of steel question

## Homework Statement

The question i need help on is question 6 part (c). I think I need to use the equation:

2. Equations used:
$$\Delta$$L = $$\alpha$$L$$\Delta$$T

Linear expansion of steel: 12x10 K^-1 ($$\alpha$$)
Density of steel: 7800

3. My attempted solution:
I tried substituting in the values into the equation but the question did not mention anything about the length of the steel so now i am stuck for a solution. I tried using proportionality with density=mass/volume so density is proportional to 1/L. However im not sure this if this is the correct way.

Thanks for your help in advance.

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## Answers and Replies

Mapes
Science Advisor
Homework Helper
Gold Member
That equation doesn't make dimensional sense; it has meters on the left but is dimensionless on the right. After that issue's fixed, you could try assuming a side length of 1 m, or 2 m. Does it make a difference?

ah, ive got it, assume it is a cube with edge length 1m, then ive got to substitute 1m in to the eqation to find the new length, then i use density = mass/volume, then i get the change in density