Answer:
Explanation:
Heat required to warm the water from 20 degree to 51 degree
= mct
= 131 x 4150 x ( 51 - 20 )
= 16853150 J
Power of heating element
= v² /R
Heat generated in 31 min
= (v² / r ) x 31 x 60 = 16853150
r = (240 x 240 x 31 x 60) / 16853150
6.35 ohm
In this case heat required will change so time will also change
Heat required =
131 x 4150 x ( 100-51 )
= 26638850 J
If time required be t hour
Energy consumed
Power x time
= (v² / r ) x t x 60 = 26638850
t = 26638850 x 6.35 / (240 x 240 x 60 )
= 48.95 h
Heat required to evaporate water at 100 degree
= mass x latent heat
= 131 x 2260000
= 296060000 J
Total heat required
= 296060000 + 26638850 + 16853150
= 339552000 J
time required = 339552000 x 6.35 / (240 x 240 x 60 )
= 623.88 h .
