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3 years ago

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6. What is the change in temperature of a metal rod that is 55.0 cm long, decreases length by 0.20 cm, and that has a coefficien

t of linear expansion of 12 x 10-6 /C?

1 answer:

MrMuchimi3 years ago

4 0

Explanation:

We have,

Length of a metal rod is 55 cm or 0.55 m

Change in length is 0.2 cm or 0.002 m

It is required to find the change in temperature of a metal rod. The coefficient of linear expansion is given by :

$\alpha =\dfrac{\Delta L}{L_0\Delta T}$

$\Delta T$ is the change in temperature

$\Delta T =\dfrac{\Delta L}{L_0\alpha }\\\\\Delta T =\dfrac{0.002}{0.55\times 12\times 10^{-6}}\\\\\Delta T= 303.03^{\circ} C$

So, the change in temperature is 303.03 degrees Celsius.

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$\begin{aligned}\text{GPE change} &= \text{Initial GPE} - \text{Final GPE} \\ &= 0 - \left(-\frac{G \cdot M_\text{e}\cdot m}{R_\text{e}}\right) = \frac{G \cdot M_\text{e}\cdot m}{R_\text{e}} \end{aligned}$

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