An electric kettle takes 4 A current at 220 V. How much time will it take to boil 1 kg of water from temperature 20 ? The temperature of boiling water is 100
- 12.6 min
- 4.2 min
- 6.3 min
- 8.4 min
Answer
(3) 6.3 min
Solution
Power P = VI = 220 4 = 880 W
Heat needed Q = ms T = 1 4200 80 = 336000 J
t = QP = 336000880 382 s
6.3 min
Answer: (3)