Potential energy and kinetic energy are types of:

CONCEPT:

Potential Energy: 

• The energy of an object obtained by doing work against the conservative forces like spring force and gravitational force is called potential energy.
• The potential energy of an object at a height h from the ground is given as

⇒ P = mgh​

Kinetic Energy: 

• The energy obtained by an object by virtue of its motion is called kinetic energy.

\(\Rightarrow K = \frac{1}{2}mv^2\)

K is kinetic energy, v is the speed of the object, m is the mass of the object.

• Mechanical Energy: The sum of potential energy and kinetic energy is called mechanical energy.

EXPLANATION:

• From the above, it is clear that the total mechanical energy is the sum of potential energy and kinetic energy. Therefore option 3 is correct.