Question

A 2 kw 40 litre water heater is switched on for 20 minutes. Heat capacity is 4.2 kj per kg-k . Increase of temperature

Answer 1

Answer:

.14.28

Explanation:

Pxt=mxcx∆t

Answer 2

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S=specific heat=energy required in joules or calories to raise temp of 1 gram

P=power of heater=1 KW=1000 watt=1000 joules/sec

! kw heater gives 1000/4.2 = 238.1Cal's per sec .