# Formula for Force

What is force? How to calculate formula for force? This article will provide all information on calculating force formula. So read on!

Narayani Karthik

Last Updated: Mar 19, 2018

What is Force?

Force is a push or a pull exerted by an energy in motion. Since Newton's laws of motion are based on the concept of force, the force is measured in Newtons (N).

Force (f) = mass (m) x acceleration (a)

where: acceleration formula is the change in velocity (v) over a period of time (t).

Force (f) = mass (m) x acceleration (a)

where: acceleration formula is the change in velocity (v) over a period of time (t).

Velocity (v) = ∆ (Distance) / ∆ (Time) = ∆ d / ∆ t

Hence, the average force formula is: Force (f) = m x a = m x v / t = m x (∆d / ∆t)

Net force = Applied Force + Frictional force

Gravitational Force Formula

What holds us to the ground? Why we don't float around in the air? The answer lies in one word: gravitational force. Newton's law on universal gravitation explains this force. When the apple fell to the ground from the tree, Newton analyzed that the force that had caused apple's fall had to be dependent on the mass of the apple. And he further deduced that the force which had caused the apple to fall was also dependent on mass of the earth.

F

_{gav}~ (product of masses of the objects) / (square of the distance between the center of the objects)

F

_{gav}= G x (m1x m2)/d

^{2}

where

G: Gravitational constant

m1: Mass of object 1

m2: Mass of object 2

d: Distance between centers of the masses of objects

(G here is the constant of proportionality and has been calculated to be about 6.673 x 10

^{-11}Newton meter

^{2}/Kg

^{2}. It is often known as the universal gravitation constant.)

*Sample Problem*:

A 70 Kg student is traveling in a plane which is flying about 40000 feet above earth's surface. Earth's mass is about 5.98 x 10

^{24}Kg. So what would be the gravitational force of attraction?

*Solution*:

40000 feet ~ 6.39 x 10

^{6}meters.

G = 6.673 x 10

^{-11}Newton meter

^{2}/Kg

^{2}

So F

_{gav}= G x (m1x m2)/d

^{2}

= 6.673 x 10

^{-11}x (5.98 x 10

^{24}x 70) / (6.39 x 10

^{6})

^{2}

= 684 N

The other fundamental forces of nature apart from the force of gravitation are electromagnetic force (force that causes repulsion, between electric charges), weak forces (the forces responsible for radioactive decay) and strong forces (which are the forces that hold the nuclei of atoms together).

Centripetal Force Formula

Have you ever sat on rides that contain swings? I bet, you must have enjoyed them in fairs. But have you ever wondered the feeling you experience in those rides is caused by what? You feel the spinning in your head, right? Well the answer lies in the term: centripetal force. So what is centripetal force? This is an unbalanced form of force that allows the object to move in a circular path towards the instantaneous center of curvature of the path traveled.

*centrum*(center) and

*petere*(towards).

F

_{centripetal}= (m x v

^{2}) / r

where

m: mass of the object

v: velocity with which the object is moving

r: radius of the path of curvature