How to calculate the coefficient of thermal expansion in% in Excel?

Question

Mathematics

There is an example, I'm trying to make a formula from it, I can't understand the solution process.

1. A steel is 40 cm long at 20 oC. The coefficient of linear expansion for steel is 12 x 10-6 (Co)-1.
The increase in length and the final length when it is at 70 oC will be…

Known :

The change in temperature (ΔT) = 70oC – 20oC = 50oC
The original length (L1) = 40 cm
Coefficient of linear expansion for steel (α) = 12 x 10-6 (Co)-1

Wanted : The change in length (ΔL) and the final length (L2)

Solution :

a) The change in length (ΔL)

ΔL = α L1 ΔT

ΔL = (12×10- 6 oC-1)(40 cm)(50oC)

ΔL = (10-6)(24 x 103) cm

ΔL = 24 x 10-3 cm

ΔL = 24 / 103 cm

ΔL = 24 / 1000 cm

ΔL = 0.024 cm

b ) The final length (L2)

L2 = L1 + ∆L

L2 = 40 cm + 0.024 cm

L2 = 40.024 cm

TOTAL - 0.06%

Anyone, in this example, what is the formula for converting from degrees to normal%?

Answer 1

(ΔL/L1)*100