INTRODUCING 5 - days-a-week problem solving session for Math Olympiad and ISI Entrance. Learn More 

October 22, 2017

Power Consumption of Electric Heater (KVPY '10)

Let's discuss a problem and know how to find the power consumption of electric heater. Try the problem and read the solution here.

The Problem:

An electric heater coonsists of a nichrome coil and under (220V)
consuming (1KW) power. Part of its coil burned out and it was reconnected after cutting off the burnt portion. The power it will consume now is:
(A) more than (1KW)
(B) less than(1KW), but not zero
(C) (1KW)
(D) 0kW

Discussion:

Part of coil is burnt. Then it was cut off. Hence resistance decreases. Hence there will be more current flow.
ELectric power $$ P=I^2R$$
Hence, power consumption will increase.

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Cheenta. Passion for Mathematics

Advanced Mathematical Science. Taught by olympians, researchers and true masters of the subject.
JOIN TRIAL
support@cheenta.com
enter