Tension Calculator

This tension calculator developed by us will teach you how to find the tension force in a rope or string used to lift an object. Or in layman language, it will help you find tension in ropes used to pull an object on a frictionless surface.

Tension scenario:
Number of ropes:
Object's mass, m:
Weight, W:
Tension in the rope, T:

What is Tension Force?

Tension force is an axial force acting perpendicularly that passes through an object that pulls, like a rope, string, or chain. The user might also observe tension force in other materials, like rods and bars, given the condition that they are subjected to external pulling or tensile loads. Materials that have high tensile strength make the best rods and bars as they don't break easily when subjected to tension forces.

How to calculate the Tension in Ropes Suspending an Object?

Following Newton's Second Law of Motion, the summation of forces using the free-body diagram of the object, as shown below. We use free-body diagrams to show the different directions and magnitudes of the forces that act on a body.

ΣF↑ = 0 = T + (-W)

T = W

Tension Free Body Diagram

T₁ = W / [cos(α) * sin(β) / cos(β) + sin(α)]

The only difference is that we first need to compute the acceleration of the entire system and sum all of the forces along the horizontal and the vertical line of motion. If the rope is at an angle from the level of the floor, we need to compute for the horizontal component of the pulling force too. T₂ = W / [cos(β) * sin(α) / cos(α) + sin(β)]

For more concepts check out physicscalculatorpro.com to get quick answers by using this free tool.

How does the Tension Calculator Work?

The calculator developed by us works in a quite easy and efficient way to get the user his answer about any question related to tension force.

  • Step 1: Enter the values of the force acting on the object in the input system of the calculator. These values should also include the angle made by the normal and the object.
  • Step 2: the calculator will itself identify if the values entered are for pulling objects or for suspended objects and hence it will use the respective formula for either of the two cases.
  • Step 3: The calculator will display the tension force as the output.

Tension Force Examples

Question 1: Calculate the tension in the string shown in the figure given below. All the surfaces are frictionless and no external force is being acted upon them. Both the blocks have a mass of 1kg. (Take gravity due to acceleration as 10m/s)


Given: the mass of each block is 1kg

And the surface is frictionless.

By the equation of motions for two blocks,



Adding these two equations we get,



Question 2: In the situation shown in the figure, calculate the tension in the string connecting the two blocks A and B (string is massless and frictional force is negligible)


Given: mass of object A is 4kg,

Mass of object B is 6kg and

10N and 30N are the respective forces acting upon the objects.

In the first block

Applying force=10N

Let, the tension between two blocks=T

Now, 10−T=4f→(1)

(where F be the acceleration of the system)

And 30−T=6f→(2)

Now solving the equation and we will get,



By solving both the equations we get, Tension (T) is 30N

FAQs on Tension Calculator

1. What is tension force?

In mechanics, tension is described as the pulling force transmitted axially by the means of a string, a cable, chain, or similar object held by some force.

2. What is the standard unit of tension force?

The standard unit of tension force is Newton represented by N

3. What force causes tension in any object?

The tension force is caused by the force that is transmitted through a cable, rope, wire, or string when it is pulled tight by forces acting from opposite ends of the object.

4. What is the tension force formula?

T = mg + ma. Where ‘m’ stands for the mass of the object and ‘a’ for the acceleration of the object.

5. What is the direction of tension force?

The direction of tension force is defined as the pull which is given the name tension in the direction of the motion of the force acting upon the object.