Difference Between Torque and Force

Last Updated : Sep 6, 2022 / By Sandeep Bhandari / Fact Checked / 4 mins

Torque is a force that is applied to any object, making it revolve around its axis. The term Torque is donated with the Greek letter ‘τ’, which is spelt as ‘tau’.

Force is stated as any action which causes motion in any object. The term is based on the three laws of Newton, along with the mass of the object and the acceleration of the object.

Comparison Table Between Torque and Force

Parameters of Comparison	Torque	Force
Definition	It is defined as the force when applied on an object that results in the rotation of it on its axis.	It is defined as any action which results in the motion of the object.
Type of Acceleration	It shows angular acceleration always.	It shows linear acceleration
Formula	τ = F × r × sin θ	F = m × a
SI Unit	Newton-meters	Newton
English Measurement Unit	Foot-pound	Pound

What is Torque?

In simple words, Torque is defined as the force acting upon an object, making it revolve around its axis. The meaning and name of the term change according to the field of study as sometimes it is referred to as moment, the moment of force, rotational force, etc. 

The Torque of an object depends upon the force acting over it, the distance between the force and the angle, and the angle on which it acts upon. In mathematical terms, the expression for calculating Torque is as follows – 

τ = F × r × sin θ

where F = the force acting upon the object 

r = the distance between the area of the force acting and the angle 

sin θ = the angle at which force is working upon

τ in the expression is known as ‘tau’ and is a Greek letter word which is used to denote the magnitude of Torque. The SI unit of the Torque is said to be Newton-meters (N-m). 

The time derivative of the Torque is said to be the angular momentum. And is known to be a pseudovector. 

Some examples of Torque based on daily lives are – 

1. When we enter a room and opens the door using the doorknob, the doorknob is rotated because of the Torque working on it. 
2. The rotation of a key in a keyhole is also one of the examples. 
3. Designing levers and combustion engines require a great knowledge of Torque.

What is Force?

Force is defined as an action that brings motion in an object or keeps it in motion. There are many types of forces that can be categorized that are – gravitational force, friction, surface tension, and many more. 

Theoretically, Force can be measured by calculating the mass of the object and the acceleration in which the object is moving continuously or moved. And in mathematical terms, it is expressed as follows – 

F = m × a

Where m = mass of the object 

a = the acceleration of the body 

The SI unit of the Force is said to be the Newton (N), while according to the English Measurement Units, Force is expressed in Pounds.

The time derivative of the Force is said to be the linear momentum. Also, it is known to be the true vector and has a specific direction of it.

Some examples of Force related to daily lives are -  

1. Walking 
2. Kicking a football
3. Pushing a box

Main Differences Between Torque and Force

1. The English Measurement Units for the Torque and Force are Foot-pound and Pound.
2. The expression via which Torque is calculated is “F × r × sin θ” whereas the force is expressed by “m × a”. 

Conclusion

Our day-to-day life depends on the forces which act between the surface. Even for the slightest or tiniest work, any type of force will be acting upon it. For example, Plants use cohesive and adhesive forces to transport water molecules within their whole plant body, meaning in leaves, fruit, root, stem.

Torque is said to be a type of force that made the object revolve on its axis, while Force is an action which only helps in the motion of any object.

The two can be important factors for any work to be done; therefore, the expression of them to express is Newton-meters and Newton.

References

1. https://www.sciencedirect.com/science/article/abs/pii/S0099239905600350
2. https://aapt.scitation.org/doi/abs/10.1119/1.16260
3. https://escholarship.org/uc/item/0w3342zg
4. https://link.springer.com/article/10.1007/s00421-002-0638-9