**Introduction:**

Reaction force is a fundamental concept in physics that describes the force exerted by an object in response to an external force applied on it. It is an essential part of structural design and engineering calculations, as it allows us to determine the amount of load that a structure can withstand. In this article, we will discuss how to calculate reaction force, and the different factors that affect it.

## What is Reaction Force?

Reaction force is a force exerted by an object in response to an external force applied on it. It is also known as the support force or contact force. When an object is placed on a surface, it exerts a force on the surface, which is equal in magnitude and opposite in direction to the force applied on the object. This force is called the reaction force.

The reaction force is important in many fields, including engineering, mechanics, and physics. For instance, when designing a bridge, engineers must consider the reaction forces acting on the structure to ensure it can withstand the weight of the vehicles passing over it.

### How to Calculate Reaction Force?

To calculate reaction force, we need to consider a few factors, such as the type of support, the load, and the dimensions of the object.

**Type of Support:**

The type of support refers to how an object is supported on a surface. There are three types of support:

**Fixed:** A fixed support prevents any movement of an object in all directions. It provides both vertical and horizontal support.

**Roller:** A roller support allows an object to move in one direction only. It provides vertical support but not horizontal support.

**Pin:** A pin support allows an object to move in two directions. It provides vertical and horizontal support.

The type of support affects the calculation of reaction force. For example, if an object is supported by a fixed support, the reaction force will be equal to the load applied on the object. However, if the object is supported by a roller or pin support, the reaction force will be less than the load applied on the object.

**Load:**

The load refers to the weight or force applied on an object. The load can be a static or dynamic load. A static load is a constant load that does not change over time, while a dynamic load varies with time.

To calculate the reaction force, we need to determine the magnitude and direction of the load applied on the object.

**Dimensions of Object:**

The dimensions of the object are essential in determining the reaction force. For example, when calculating the reaction force on a beam, we need to consider the length, width, and height of the beam. The dimensions of the object affect its weight, which determines the load applied on the object.

Once we have determined the type of support, load, and dimensions of the object, we can use the equations below to calculate the reaction force:

**Fixed Support:** Reaction Force = Load Applied

**Roller Support:** Reaction Force = Load Applied / 2

**Pin Support:** Reaction Force = Load Applied / √2

### What is the formula of reaction force?

The formula for calculating reaction force depends on the type of support that an object is resting on. There are three types of support: fixed, roller, and pin. For a fixed support, the reaction force is equal to the load applied on the object. For a roller support, the reaction force is half the load applied on the object. And for a pin support, the reaction force is the load applied on the object divided by the square root of 2.

### How do you calculate action and reaction forces?

Action and reaction forces are two equal and opposite forces that occur in pairs when two objects interact with each other. To calculate these forces, we need to apply Newton’s Third Law, which states that for every action, there is an equal and opposite reaction. Thus, if object A exerts a force on object B, then object B exerts an equal and opposite force on object A.

### Why do we calculate reaction forces?

We calculate reaction forces to determine the amount of load that a structure can withstand. Reaction forces are essential in structural design and engineering calculations, as they allow us to ensure that structures are strong and safe for use.

### What is the reaction force?

Reaction force is the force exerted by an object in response to an external force applied on it. It is also known as the support force or contact force. When an object is placed on a surface, it exerts a force on the surface, which is equal in magnitude and opposite in direction to the force applied on the object. This force is called the reaction force.

### How to calculate reaction forces on beams?

To calculate the reaction forces on beams, we need to consider the type of support, load, and dimensions of the beam. We can then use the equations mentioned earlier to calculate the reaction forces.

### How to calculate reaction forces on beams pdf?

There are many resources available online in PDF format that explain how to calculate reaction forces on beams. These resources provide step-by-step instructions and diagrams to help readers understand the process.

### Ground reaction force formula?

The ground reaction force formula refers to the force exerted by the ground on an object in contact with it. This force is equal in magnitude but opposite in direction to the force applied on the ground by the object. The formula for ground reaction force is F = ma, where F is the force, m is the mass of the object, and a is the acceleration of the object.

### How to find reaction force at pivot?

To find the reaction force at a pivot, we need to consider the type of support and load applied on the object. We can then use the equations mentioned earlier to calculate the reaction force.

### How to calculate reaction forces on a truss?

To calculate the reaction forces on a truss, we need to consider the type of support, load, and dimensions of the truss. We can then use the equations mentioned earlier to calculate the reaction forces.

### Normal reaction force formula?

The normal reaction force formula refers to the force exerted perpendicular to the surface by an object in contact with it. The formula for normal reaction force is F = mg cosθ, where F is the force, m is the mass of the object, g is the acceleration due to gravity, and θ is the angle between the surface and the object.

### Reaction moment formula?

The reaction moment formula refers to the torque or moment created by the reaction force at a support point. The formula for reaction moment is M = F x d, where M is the moment, F is the force, and d is the distance from the support point to the line of action of the force.

### How to calculate reaction force in a cantilever beam?

To calculate the reaction force in a cantilever beam, we need to consider the type of support, load, and dimensions of the beam. We can then use the equations mentioned earlier to calculate the reaction force. In a cantilever beam, the reaction force is equal to the load applied on the beam.

### What is a reaction force?

A reaction force is the force that an object applies in response to the force applied on it by another object.

### How do I calculate reaction force?

The calculation of reaction force depends on the situation and the nature of the forces involved. Here are a few general ways to calculate reaction force:

When two objects are in contact, the reaction force is equal in magnitude and opposite in direction to the force applied. For example, if a ball is dropped on the ground, the reaction force exerted by the ground on the ball is equal to the force with which the ball hits the ground.

In a statics problem, you can calculate the reaction force by applying Newton’s third law of motion, which states that for every action, there is an equal and opposite reaction. This means that the sum of all the forces acting on an object must be zero. So, if you know the forces acting on an object, you can use this principle to calculate the reaction force.

If you know the coefficient of friction between two objects, you can calculate the reaction force using the formula F = μN, where F is the force of friction, μ is the coefficient of friction, and N is the normal force (the force perpendicular to the surface of contact).

### Are there any online tools or calculators available to help me calculate reaction force?

Yes, there are several online calculators and tools available to help you calculate reaction force based on different scenarios. However, it’s important to note that these tools may not always provide accurate results, especially if the situation is complex or involves multiple forces acting on an object. Therefore, it’s recommended to have a basic understanding of the underlying principles and equations involved in calculating reaction force.

## Conclusion:

In conclusion, reaction force is an important concept in physics and engineering. It allows us to determine the amount of load that a structure can withstand. To calculate the reaction force, we need to consider the type of support, load, and dimensions of the object. By understanding these factors, engineers and designers can create structures that are strong and safe for use.