A mixer–grinder has a metal outer casing that is firmly connected to the earth…
PHYSICS · Multi-part · CBSE · Physics · Magnetic Effects of Electric Current · Magnetic Effects of Electric Current
Problem
A mixer–grinder has a metal outer casing that is firmly connected to the earth terminal in the three-pin plug supplied with the appliance. Consider the following situation to answer the questions that follow.
(i) Explain why connecting the metal casing of the mixer–grinder to the earth terminal protects a user from electric shock under normal working conditions.
(ii) The insulation on the live wire inside the mixer–grinder wears out and the conductor touches the metal casing. Describe, with reason, what will happen to the potential of the casing immediately after this fault if the earth connection is present.
(iii) If the same fault occurs but the earth connection is missing, predict what would happen to the potential of the casing and to a person who touches it. Justify your answer.