pls explain

Asked by sulaikhasulu393 | 30th Apr, 2020, 09:27: PM

Expert Answer:

Wire of resistance 20 Ω covered with ice and voltage of 210 V is applied across the wire 
 
rate of heat produced is given as, 
 
H = V2 / R 
 
Thus, 
 
H = (210)2/ 20 = 2205 J/s
 
Latent Heat of fusion of ice = 80 cal/g 
 
Thus, we can convert heat produced in cal/s by dividing it with 4.2 cal
 
Thus, 
H equals fraction numerator 2205 over denominator 4.2 end fraction c a l divided by s

L e t comma space m space b e space t h e space m a s s space o f space i c e space m e l t i n g space p e r space s e c o n d comma space

m L space space equals space fraction numerator 2205 over denominator 4.2 end fraction
m space cross times space 80 space equals space fraction numerator 2205 over denominator 4.2 end fraction
m space equals space fraction numerator 2205 over denominator 4.2 cross times 80 end fraction space equals space 6.5 space g divided by s space 
 
Thus, rate of melting of ice is 6.5 g/s 
 
 

Answered by Shiwani Sawant | 30th Apr, 2020, 10:45: PM