An electric drill rated 400W is used to drill a hole in copper of mass 400g in 20s. Calculate the rise in temperature if all the heat produced is absorbed by the copper. [specific heat capacity of copper = 400Jkg-1K-1]
-
A.
100oC -
B.
75oC -
C.
50oC -
D.
45oC
Correct Answer: Option C
Explanation
(theta = frac{Pt}{MC} = frac{400 times 20}{0.4 times 400} = 50^o)