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How long will it take 240V, 3000W electric immersion heater to raise the temperature of 150 litres of water in a well-lagged calorimeter made of copper of mass 20kg from 15° to 70°C?​

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Answer:

Q = mcΔT

Where:

Q is the heat energy transferred

m is the mass of the water

c is the specific heat capacity of water

ΔT is the change in temperature

First, let's calculate the heat energy required to raise the temperature of the water:

Q = mcΔT

m = 150 kg (since 1 liter of water is approximately equal to 1 kg)

c = 4186 J/kg°C (specific heat capacity of water)

ΔT = 70°C - 15°C = 55°C

Q = (150 kg) * (4186 J/kg°C) * (55°C)

Q = 346,185,000 J

Now, let's calculate the time using the power of the electric immersion heater:

P = W/t

P = 3000 W (power of the heater)

We can rearrange the formula to solve for time:

t = W/P

t = Q/P

t = (346,185,000 J) / (3000 W)

t ≈ 115,395 seconds

User Jagadesh Seeram
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