A contact force is a force exerted by things that come into contact with one another. The impact force exerted at the point when the two items come into close contact may be constant in the form of a continuous force or momentary in the form of an impulse. Newton’s Laws regulate the power of contact. Much of the experiences we have in our everyday lives are related to contact power. Touch power, such as driving a vehicle up a slope, writing your name with a marker, or picking up a textbook from the table, are both instances of continuous force. Hammering a nail, throwing a ball, and other related acts are manifestations of instinct or momentary energy.

A force applied to an entity by a body that is not in physical interaction with it is a non-contact force. When objects do not directly contact one another or when a force is exerted without interaction, non-contact forces are present. There are very few non-contact forces as opposed to the many forms of fighting forces.

A circular motion is a body movement that follows a circular direction. Uniform Circular Motion is the motion of a body travelling at a constant speed around a circular path. The speed is steady, but the velocity varies.

Multipliers Energy Sources are classified into two categories:

• Kinetic Energy: The force correlated with an object’s motion is known as kinetic energy. Objects in motion can make a shift or do work.
• Potential Energy: The energy contained in an individual or system is potential energy. Potential energy may be transformed into a more measurable source of kinetic energy.

The force that can trigger an object to rotate around an axis is represented in torque. In linear kinematics, force is what allows an entity to accelerate. Torque is also responsible for angular acceleration. As a consequence, torque is the linear force’s rotational counterpart. The axis of rotation is the position at which the object rotates. Torque is the ability of a force to transform or rotate in mechanics. Torque is defined using some terminologies, including moment and moment of power.

Energy cannot be produced or lost, according to the law of conservation of energy. It may, however, be modified from one shape to another. The cumulative energy of an isolated object stays unchanged as all sources of energy are included. The rule of conservation of energy applies to all sources of energy. In a nutshell, the law of conservation of energy says that the overall energy of a closed system, one separated from its environment, is conserved.

If there is depletion of energy in one portion of an isolated structure, there must be a gain of energy in another part of the universe. There is no known cause of a breach of the law of conservation of energy, considering the reality that this theory cannot be confirmed.

Several electrical and mechanical systems work strictly on the principle of energy conservation. Below mentioned are a few examples of energy conservation:

• The chemical energy of the batteries is transformed into electrical energy in a torch, which is then converted into light and heat.
• Water falls from a height on the generators of hydroelectric power stations. It allows the turbines to spin and produce electricity. As a result, water’s potential energy is transformed into the turbine’s kinetic energy, which is then converted into electrical energy.
• Electrical energy is transformed into sound energy in a loudspeaker.
• Sound energy is transformed into electrical energy in a microphone.
• Mechanical energy is transformed into electrical energy in an engine.
• Chemical energy is transformed into heat and light energy as fuels are burned.
• When food breaks down in the body, chemical energy is transferred to thermal energy to maintain the body warmth.

In this chapter, we learned about the basic concepts of Force, Work, Energy and Power. We learned about the types of forces and the energy conservation principle.

1. What is the SI work unit?
   The Joule is the SI unit of work. When a force of one Newton displaces the body by one metre in the direction of the force, work is completed.
2. Is force a source of energy?
   The terms “energy” and “power” are not interchangeable; they are not identical.
3. Is power the same as work?
   Work is the amount of energy used to apply a force to transfer an object to a certain distance, where the force is parallel to the displacement. The rate at which work is performed is power.
4. What are the energy types?
   There are several different types of resources, but they all fall into one of two categories:
   1. Potential energy
   2. Kinetic energy
5. What is the power unit?
   Watt