Question

In a three-pin plug, why is the earth pin made longer and thicker than the other two pins?

Answer 1

The earth pin being thicker can never enter live or neutral sockets thereby ensuring that the electric appliance would always be connected in one proper position, where the live, the neutral and the earth wires are connected properly. Also, the earth pin being longer, will be the first to get connected to earth terminal. This would save the user from getting any electric shock, because the current will melt the fuse in case the electrical appliance is short-circuited.