Question

1)of three wires of household circuit which two of them aren't the same potential?
2) which class of lever has mechanical advantage greater than 1
b) what change can be brought about in the lever to increase the mechanical advantage​

Answer 1

Of the three wires of household circuit the two of them which are at the same potential are neutral wire and Earth wire.

Second class of lever has mechanical advantage greater than 1.

In order to increase the mechanical advantage the length of the load arm can be shortened by moving the load towards the fulcrum.