Question

How much electricity is used to boil 600 g of water if the kettle has a power of 1500 W? The water boiled for 3 minutes and 9 seconds. Water density is 1000 kg/m3, specific heat of water is 4200 J/(kg· oC).

Answer 1

Answer:

The electrical energy consumed in boiling the water is 0.0788 kWh

Explanation:

Given;

mass of the water, m = 600 g = 0.6 kg

power rating of the kettle, P = 1500 W = 1.5 kW

specific heat capacity of water, c = 4,200 J/kg⁰C

density of water, = 1000 kg/m³

time taken to boil the water, t = 3 mins + 9 s = (3 x 60s) + 9 s = 180 s + 9 s = 189 s = $189 \ s \times \frac{1 hr}{3.600 \ s} = 0.0525 \ hr$

The electrical energy consumed in boiling the water is calculated as;

E = P x t

E = 1.5 kW  x 0.0525 hr

E = 0.0788 kWh

Therefore, the electrical energy consumed in boiling the water is 0.0788 kWh