An electric heater has a power of 1000W. It is connected to mains electricity (230V). The heater is equipped with an Earth wire. a) Calculate the current in the heater. b) Explain the role of the earth wire as a safety feature.

a) Use the equation P=IV where P is power in W, I is Current in Amps and V is voltage in volts. Rearrange to give I=P/V I=1000/230 = 4.34 A b) This is a wire connected to the metal casing of an electrical appliance. If the casing becomes live it provides a low resistance path to earth. The large current in the earth wire causes the fuse to blow causing the current to stop. This prevents electrocution. 

KS
Answered by Katie S. Physics tutor

14371 Views

See similar Physics GCSE tutors

Related Physics GCSE answers

All answers ▸

Name two properties that both microwave and infrared has.


State Newton's 3 Laws in words and/or mathematically


a )John heats up 2kg of water from 20 degrees c to 80 degrees c. How much energy input did this require? b )When John weighs the water at the end, he has less than he started with. Why might this be? c) What hazards are in this experiment?


Using newtons laws explain how a falling object can reach terminal velocity (6)


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences