Question

A copper sphere was moving at 25 m/s when it hit another object. This caused all of the KE to be converted into thermal energy for the copper sphere. If the specific heat capacity of copper is 387 J/(kg ⋅ C°), what was the increase in temperature?

0.23 C°
0.81 C°
1.3 C°
2.1 C°

Answer 1

Answer:

$\Delta T = 0.81 ^oC$

Explanation:

As we know by energy conservation

All its kinetic energy will convert into thermal energy to raise its temperature

$\frac{1}{2}mv^2 = ms\Delta T$

now divide both sides by mass of the object

$\frac{1}{2}v^2 = s\Delta T$

so change in temperature is given as

$\Delta T = \frac{v^2}{2s}$

$\Delta T = \frac{25^2}{2\times 387}$

$\Delta T = 0.81^oC$