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Relationship between Force and Motion

Force and Motion relationship, definition, formula and examples.

Physics has exposed to us the different motion of a body. How motion occurs on objects, how an object under motion can be stopped. All these have been explained in my previous article. Well, the answer beyond all these is Force. Force and motion work hand on hand. Let have a brief knowledge of Force and Motion as well as their relation.


Force is said to be an attribute of physical action or movement or a push or pull acting on an object. It occurs when to items are in contact. The universal law of gravitation has explained that every object in this universe exerts a force on others. It is given by the following parameter:

  • SI unit of Force: newton(N) or kg.m/s2
  • Symbol of Force: F
  • Type of quantity: Vector quantity
  • Dimensional Formula: M1L1T-2
  • Other units: dyne, pound-force, kilopond, poundal, kip

In physic, objects are said to exert forces on each other, when there are two objects of mass M and m. if these objects are kept in a way that the object with mass m is placed over the object with mass M. this is to say, there is a force of interaction when two or more bodies are kept on each other.

Force and motion


The movement of an object or body is known as motion. For example, when a taxi driver carries passengers from one spot to another. In this situation, the car is in motion. Just imagine the car stop to drop or carry another passenger for some minute. At this moment there is no motion in the body, so this implies that motion is dependent on time. Remember, Physics have explained that motion is the change in the position of a body with respect to time.

Force and motion relationship

The formula of Force and Motion


Relationship between Force and Motion

Force can be simply explained as the cause of motion. They are intensely related in nature because without force motion can’t occur. For instance, if a person is walking, there is motion caused by force, making the person move. This force is known as the muscular force of the body.

We earlier explained that force can simply be a push or a pull acting on a body. It is defined as any interaction that, when applied, it changes the motion of an object. This is to say force affects the state of motion of an object.

Discussing what it meant by the state of motion, it refers to the movement of a body. Generally, it can be described as

  • Change in speed, or
  • Change in direction.

The relationship between force and motion is that force affects the state of motion. It can cause motion to happen and it can cause it to stop. For instance, if a vehicle is moving under motion, it can stop by the force applied by the break.

The first person to discover the relationship between motion and force was Sir Isaac Newton. From his studies in force and law of motion, which we arrive at the following conditions:

  • Force can accelerate the body
  • Force decelerate the body
  • Force can change the direction of the moving body

How Force can Cause a Body to Accelerate

Force is applied to a body at rest, it begins to move and accelerates. The acceleration can be described as a positive change in velocity over a period of time.

If force is applied in the same direction of movement of a moving object, it accelerates. For example, if the pedal of a bicycle is rotated, the bicycle moves faster.

How Force can Cause a Body to Decelerate

Force can cause a body to decelerate if a force is applied in the opposite direction of the moving object. It will slow down and eventually stop if the force is continued to be applied. For instance, if a shot is played and the goalkeeper stops the call, the ball is caused to decelerate and stop.

How Force can Cause a Body to Change Directions

Force can change directions of an object if the force is applied to it at a different angle. This causes the object to change in direction of motion. This principle is found in almost all sport that uses a ball. The speed can be maintained if the force is applied in a perpendicular angle but the velocity will change. Now you can see there is an intimate relationship between force and motion.

I hope you’ve found this post interesting and attained the knowledge. If so, you can freely give your point in our comment section and please share with other students. Thanks!

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