Force is exerted when two objects interact with each other, while power is equal to the energy consumed over time to do work. In this article, we will discuss the important differences between force and power.
Sometimes, force and power create confusion because they seem the same. Although, actually they are completely different from each other. The fundamental difference between force and power is that force is a cause that changes or tends to change the state of a body, while power is the rate of doing work, i.e. energy consumed by a body per unit of time while doing work.
Before going into the differentiation of force and power, let us first discuss a bit about force and power individually.
What is Force?
The physical cause that brings or tends to bring a change in the state of a body on which it is acting is referred to as force. Therefore, force is the factor that can change the state of the body either from rest to motion or motion to rest.
Force can be the result of direct or indirect interaction between two bodies. Mathematically, the force can be defined as the product of the mass of the body and acceleration produced in the body due to the action of force on the body, i.e.
The SI unit of force is Newton (N). The force applied on a body is said to be 1 N if the body has a mass equal to 1 kg, and the body has an acceleration of 1 m/s2 due to the action of the force. Force is a vector quantity, therefore, it has magnitude as well as direction.
Based on the application, force may be classified into the following two types namely,
- Contact Force – When forces act on a body by making direct contact or contact through a medium with the body is referred to as a direct force. For example, frictional force, air drag, mechanical forces, etc.
- Non-Contact Force – Non-contact force is one that acts without making a direct connection with the object, i.e. act through space. For example, gravitational force, magnetic force, electric force, etc.
What is Power?
Power is defined as the rate of doing work. In other words, the amount of energy expended to perform work per unit of time is known as power.
Therefore, power can be mathematically expressed as,
The SI unit of power is Watt. When 1 joule of work is done in 1 second, then power is said to be of 1 watt.
Depending on the type of system, power can be of two types namely, electrical power (examples average power, instantaneous power, reactive power, apparent power, etc.), and mechanical power (examples hydraulic power, wind power, etc.)
After getting the basic insights about force and power, let us now discuss the differences between force and power.
Differences between Force and Power
The important differences between force and power according to different factors are listed in the following table:
| Factor | Force | Power |
| Basic Definition | The physical that causes a change in the state (rest or motion) of a body is known as force. | The rate of work done, i.e. work done per unit of time is known as power. |
| Symbolic Representation | Force is denoted by the symbol F or F. | Power is denoted by the symbol P. |
| Formula | Force is given by the following formula, F = m x a | Power is given by the following formula, P= W/t |
| SI Unit | The SI unit of force is Newton (N). The unit was named in the honor of Sir Isaac Newton. | The SI unit of power is Watt (W). The unit is named in the honor of James Watt. |
| Relationship with Work | Force is related to work as follows: “Work is done when force is applied to a body and the body is displaced by a distance.” | Power is related to work as follows: “Power specifies the rate of work done.” |
| Nature of quantity | Force is a vector quantity, i.e. it has both magnitude and direction. | Power is a scalar quantity because it has only magnitude. |
| Types | Forces are classified into two types namely, Contact forces (mechanical force, frictional force, etc.) Non-contact forces (gravitational force, magnetic force, electrostatic force, etc.). | Power is classified into two types namely, Mechanical power (wind power, hydraulic power, etc.) Electrical power (DC power, AC power, etc.). |
Conclusion
Thus, this is all about the differences between force and power. From the above comparison, we may conclude that force and power are two absolutely different physical quantities. The one most significant difference that can be stated from the above comparison is that force is responsible for changing the state of a body, whereas power gives information about the rate at which work is being done.