W = F × s = 20 N × 3 m = 60 J

GPE = m × g × h

where m is the mass of the object and v is its velocity.

A machine requires an input energy of 2000 J to lift a 50 kg load to a height of 2 m. If the machine takes 5 seconds to lift the load, calculate its efficiency.

Solution:

Gravitational potential energy is the energy an object possesses due to its height above the ground. The gravitational potential energy (GPE) of an object is given by the equation:

Kinetic energy is the energy of motion. An object possesses kinetic energy when it is moving. The kinetic energy (KE) of an object is given by the equation:

Then, calculate the efficiency:

GPE = m × g × h = 5 kg × 9.8 m/s^2 × 2 m = 98 J

Potential energy is the energy an object possesses due to its position or configuration. There are two main types of potential energy: gravitational potential energy and elastic potential energy.