1.0 kg of water is contained in 1.25 kW kettle. Calculate the time taken for the temperature of water to rise from 25°C to its boiling point 100°C . Specific heat capacity of water.
Answers
Answered by
115
Let the time taken is t
heat loss by kettle = heat gain by water
1.25 × 10³ × t = Q = mC∆T
C is the specific heat capacity of water e.g., C = 42J/Kg/K
∆T = (100 - 25)°C
1250 × t = 1 × 4200× ( 100 - 25)
1250 × t = 4200 × 75
50t = 12600
t = 1260/5 = 252 sec
hence, time taken = 252 sec
heat loss by kettle = heat gain by water
1.25 × 10³ × t = Q = mC∆T
C is the specific heat capacity of water e.g., C = 42J/Kg/K
∆T = (100 - 25)°C
1250 × t = 1 × 4200× ( 100 - 25)
1250 × t = 4200 × 75
50t = 12600
t = 1260/5 = 252 sec
hence, time taken = 252 sec
Answered by
56
Hey there!
Heat energy required for 1 kg of water to raise its temperature from 25°C to 100°C = mCΔt
here,
m = 1 kg = 1000 g
C = 4.2 J/( g . K)
Δt = 100° - 25° = 75°
Heat required = 1000 * 4.2 * 75 = 315000 J
Now,
Power = 1.25 kW = 1250 W
Power = Heat / time
1250 = 315000 / t
t = 315000 / 1250
t = 252 sec
t = 252 / 60 minute
t = 4.2 min
t = 4 min 2 sec
Similar questions