Entry Test MCQ :: Current Electricity

@ : Home > Physics > Current Electricity

An immersion heater of 400 watts kept on for 5 hours will consume electrical power of

[A].	2KWh	[B].	20KWh
[C].	6KWh	[D].	12KWh

Answer: Option A

Umar said:

the answer is not A in fact answer is B(20KWH). we know BTu is KWH then 4001000/36005=20KWH

Sairah said:

well i did it like this dont know whether ri8 or wrong 400*5/1000...kindly tell which way it is ri8..??:/:/:/

Doctor said:

Since heat=power×time,so 400×5×3600/36×10e5=2kwatt