Question

heater is used for 5 minutes to heat 500g of water from 30°C to 30°C. what is the power of heater? specific heat capacity of water is 4.2J/g°C.

kindly explain step by step​

Answer 1

Answer:

Time = 5 minutes

Let power of heater = P

Energy supplied by heater= P×t

=P×300

Also, rise in. temperature of water θR

=Final temperature- Initial temperature

=0 degree C

∴ Heat energy absorbed by water

=mcθ

R

=500g×4.2Jg

−1

−1

×0

o

C

=21000J

∴ By the law of conservation of energy,

By the law of conservation of energy,P×300s=21000J

∴P=

300

21000J

=219Js

−1

orwatt

 

Explanation: