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# An aluminium rod of length 1.8m at 100oC is heated to proceed pr...

### Question

An aluminium rod of length 1.8m at 100oC is heated to proceed produce a difference in length of 0.007m. Calculate the temperature to which it is heated. (Linear expansivity of aluminium = 2.3 x 10-5K-1

A) 155oC

B) 160oC

C) 169oC

D) 179oC

### Explanation:

$$\alpha = \frac{L_2 - L_1}{L_1(\theta_2 - \theta_1)}$$

L2 - L1 = $$\alpha L_1 (\theta_2 - \theta_1)$$

$$\theta_2 = \frac{0.007}{2.3 \times 10^{-5} \times 1.8}$$ + 10

= 179oC

## Dicussion (1)

• $$\alpha = \frac{L_2 - L_1}{L_1(\theta_2 - \theta_1)}$$

L2 - L1 = $$\alpha L_1 (\theta_2 - \theta_1)$$

$$\theta_2 = \frac{0.007}{2.3 \times 10^{-5} \times 1.8}$$ + 10

= 179oC