An electric kettle is used to heat water.
The kettle is plugged into the mains supply and turned on. Explain why the temperature of the water increases. Write about energy stores in your answer.
The temperature of the water increases from 15∘C15^\circ\text{C}15∘C to 95∘C95^\circ\text{C}95∘C. The mass of water is 1.5 kg1.5\text{ kg}1.5 kg. The specific heat capacity of water is 4200 J/kg∘C4200\text{ J/kg}^\circ\text{C}4200 J/kg∘C.
Calculate the energy required to increase the temperature of the water. Use the equation:
change in thermal energy=mass×specific heat capacity×change in temperature \text{change in thermal energy} = \text{mass} \times \text{specific heat capacity} \times \text{change in temperature} change in thermal energy=mass×specific heat capacity×change in temperatureThe power of the kettle is 2300 W2300\text{ W}2300 W. The potential difference of the mains supply is 230 V230\text{ V}230 V.
Calculate the current in the heating element of the kettle. Use the equation:
power=potential difference×current \text{power} = \text{potential difference} \times \text{current} power=potential difference×currentA designer suggests, 'We should use a heating element with a higher current.' Suggest two reasons why this is a good idea.
The kettle has an outer case made of metal.
Which wire(s) should be connected in the electric plug of the kettle? Select all that apply: