A 2000W electric heater is used to heat a metal object of mass 5kg initially at 10°C. If a temperature rise of 30°C is obtained after 10min; the heat capacity of the material is?

A. 6.0 x 10⁴JC^-1
B. 4.0 x 10⁴JC^-1
C. 1.2 x 10⁴JC^-1
D. 8.0 x 10⁴JC^-1

Correct Answer:

Option A – 6.0 x 10⁴JC^-1

Explanation

2000W heater → 2000J/S
=> Heat supplied by the heater within 10 min
(600 seconds) = 2000 x 600
= 1200000J
∴ Heat capacity MC = 1200000/(30-10)
= 60000J/C
Heat capacity = 6.0 x 10⁴JC^-1