An immersion heater of an electric coffee maker operates at 120V with a current of 4.17A. Suppose that 80% of the heat is absorbed by the water.

a) Find the time it will take to heat 2 liters of water from the temperature of 20C to its boiling 100C. Water specific heat: 4180 J/(K.kg) (Answer: 27.8 min).

b) If by carelessness the heater was not turned off, calculate how long more will evaporate half the water. Latent Evaporative Heat: 2256.103J/kg (Answer: 1.56 h)

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