# Magnitude of Force

An external or internal agent that acts to bring about a change in the physical appearance or motion of a body is known as a force, We will discuss the magnitude of the forces The magnitude of the force is the measure of its power to bring about the necessary change. Force has magnitude and also acts in a particular direction. The force can be contact or non-contact. Almost all day-to-day work is done by exerting some form of force.

When we push, pull or lift an object, the measure of the force required to do that work is known as its magnitude. Other forces such as friction, gravitational pull. Stress have magnitude as well as their size. For example, a muscle exerts some degree of force to extract the juice from a lemon. When a ball falls down because of gravity pulls it towards the ground, These are the magnitudes of all forces, The second law of motion is considered to produce a general formula for the magnitudes of the force. It states that the magnitudes of the force applied to move an object is equal to its rate of change of momentum, i.e.:

F\propto \frac{\mathrm{dp} }{\mathrm{d} t}

F= k \frac{\mathrm{dp} }{\mathrm{d} t}

Here,

F = magnitude of force

k = constant

p = momentum i.e., m a

The value of k is taken as unity, and therefore the formula for the force is:

F=\frac{\mathrm{d(mv)} }{\mathrm{d} t}
F=m\frac{\mathrm{d(v)} }{\mathrm{d} t}

since,\frac{\mathrm{dv} }{\mathrm{d} t}= a



F = ma

The SI unit of force is N, i.e. Newton.

## effect of magnitude of force

Force has various effects on an object. When a force of sufficient measure is applied to a body or object, one of the following five effects appears:

• move a stationary object
• stops a moving object
• change the direction of a moving object
• resize object
• change the velocity of the object

### Move a stationary object .

A stationary object remains in that state until an external agent acts on it. On applying a force on a stationary body, it starts to displace from its position and comes into motion. The magnitude of the forces determines how much the object will move and with what velocity.

For example, a ball placed on the ground remains in a state of rest. When someone kicks it, it comes into motion. The ball is accelerated at a rate proportional to the intensity with which it is kicked. Hence the force accelerates the stationary object.

### stops a moving object

Another effect of the magnitude of the force on an object is its stopping motion. By applying force on a moving body. It can come to rest. The magnitude of the force required to stop a moving body mainly depends on the mass of the body. Stopping a moving elephant would require several people to simultaneously apply a force and generate a high magnitude. Whereas stopping a moving ball would require only one person and much less force. This is because the mass of the elephant is much greater than that of the ball, and thus more force is needed to stop it.

### Change the direction of a moving object .

A moving body can change its direction after experiencing a force. After hitting the wall the moving ball bounces back and changes direction. When a ball hits a wall, a force is exerted on it and it is pushed backwards.

### The size or shape of the object changes .

The magnitude of the force can also change the shape or size of the object. It can increase or decrease the length. There is also a change in the shape of the body, but sometimes this change is so subtle that it is not visible to the eyes.

When we stretch a rubber band long enough, the rubber lengthens. That is, by applying force, its shape changes. Similarly, the shape of a lemon gets distorted when it is squeezed. So it is clear from these examples that force shows effect on the shape and size of an object.

### Change the velocity of the object .

An object that is in motion can move or move when a force is applied to it. When a force is transmitted to a moving body, its velocity changes. A cyclist pushing a bicycle already riding accelerates it when the velocity increases.

### What is strength?

The energy or force acting internally or externally to change the position of the body is known as force.

In simple words, the force applied to any object to change its velocity, shape or position is known as force. We experience force or exert it in some form or the other. Opening a door or lifting a pencil are examples of force.

### Is force a scalar or a vector quantity?

Those fundamental quantities which have only magnitude are called scalar quantities. Whereas are vector quantities having magnitude and direction. The force is known as a vector quantity.

### What is the magnitude of the force?

Force is the energy or thrust that is applied to an object.

The force or size of a force acting on a body is its magnitude. This is the numerical value of the force. The amount of force a human muscle would need to lift a box would be considered a measure of force.

### How is the magnitude of the force obtained?

The measure of force is known as its magnitude.

Using Newton’s second law, the formula for the magnitude of the force is prepared . According to the law, the magnitude of the force is directly proportional to the rate of momentum.

ie; F\propto \frac{\mathrm{dp} }{\mathrm{d} t}

Therefore, we get the formula;

F = ma

## What is an example of magnitude of force?

All our day to day activities can be explained by the concept of force. Either force acts on us, or we apply it.

Force should be applied to squeeze out the toothpaste. This force is of push type as the person has to push the paste outwards. It is pressed between the fingers. This is a common example of muscular force. The shape of the paste gets distorted under the influence of force.

### What are the effects of magnitude of force?

A force can have the following five effects on a body:

• change size and shape
• change velocity
• change direction
• stop a moving object
• move a stationary object

### On what factors does the magnitude of the force depend?

The amount of force is known as the magnitude of the force. It’s basically the size of the force.

The magnitude of the force applied depends on the mass and displacement of the object. The greater the mass of the body, the greater the magnitude of the force to push or pull it.

### What is the SI unit of magnitude of force?

The standard unit of magnitude of force is named after Isaac Newton. Hence, its SI unit is N, Newton.