Net Force Formula

The net force is the force which is the sum of all the forces acting on an object simultaneously. Net force can accelerate a mass. Some of the other forces act on anybody either at rest or motion. The net force is a term used in a system with multiple forces. In this article, we will define net force, and then explore the net force formula with examples. The relevant equations and formulas will help to make the concept of net force clearer. Let us learn it!

Source:en.wikipedia.org

Net Force Formula

Definition of a Net Force

When we kick a soccer ball, then the ball takes off and moves through the air. Then, there is a net force acting on the ball. Again when the ball starts to come back to the ground and eventually stops, there is also a net force acting on the ball.

According to Newton’s Second Law, when a net force is acting on an object, then that object must be accelerating. Therefore, its speed changes from second to second. Hence when we first kick the soccer ball, it accelerates, and when the soccer ball begins to slow down it is again accelerating.

Now, a net force is defined as the sum of all the forces acting on an object. The following equation is the sum of N forces acting on an object.

\(F_Net = F_1 + F_2 + F_3….+ F_N \)

Where,

\( F_1, F_2, F_3….FN\) are the forces acting on a body.

When the body is at rest position then the net force formula is given by,

\(F_Net = F_a + F_g\)

Where,

\(F_Net\)	Net force
\(F_a\)	Applied force
\(F_g\)	Gravitational force

Now, we will find the Net force when a body is in motion. When a force is applied on the body, then with the applied force, other forces like gravitational force, frictional force, and the normal force also work.

The net force formula:

\(F_Net = F_a + F_g + F_f + F_N\)

Where,

\(F_Net\)	Net force
\(F_a\)	Applied force
\(F_g\)	Gravitational force
\(F_f\)	Frictional force
\(F_N\)	Normal force.

According to Newton’s Second Law, for an accelerating object, some force must be a net force acting on it. Conversely, we may say if a net force acts on an object, that object will accelerate. The magnitude of the net force acting on an object can be computed as the product of the mass of the object with the acceleration of the object. Thus,

\(F_NET = m \times a\)

\(F_Net\)	Net force
m	Mass
a	Acceleration

 If the net force acting on an object is zero, then the object is not accelerating and is in a state that we call equilibrium. Then the formula will be,

\(F_NET = 0\)

Solved Examples

Q.1: In a tug of war, a fat man pulls with a force of 100 N on one side, and a man pulls with 90 N on the other side. Compute the net force.

Solution:

Given:

Force F1= 100 N,

Force F2 = -90 N.

The net force formula is given by,

\(F_NET = F_1 + F_2\)

\(F_NET = (100 ) +(– 90)\)

\(F_NET= 10 N \)

Therefore, the net force is 10 N.