Mechanical energy is the sum of the energy of an object

The correct answer of this question is : Sum of kinetic as well as potential energy.

EXPLANATION:

The body has two types of mechanical energy which are known as kinetic energy and potential energy.

The potential energy of a body is defined as the energy gained by the body by virtue of its position or change in configuration.

The energy due to the position of the body from surface is known as gravitational potential energy, and the energy due to change in configuration is known as elastic potential energy.

The kinetic energy of a body is defined as the energy gained by the body due to its motion.

The sum total of kinetic energy and potential energy of a body is known as mechanical energy.

Hence,  mechanical energy = Kinetic energy + potential energy.

r=rho l/a where a is the area, l is the length and rho is resistivity so the greater the area the lesser the resistance thats why the earth pin is thicker bcos current follow the shortest path, so less resistive .