Types of forces

The information on this page is ✔ fact-checked.

Types of forces
Types of forces

In physics, forces are broadly categorized into two main types: contact forces and non-contact forces. Contact forces result from direct physical interaction between objects, such as friction and tension, while non-contact forces, like gravity and magnetic forces, act at a distance without physical contact between objects.

Contact force

Types of forces - contact force
Collecting garbage from the floor involves contact force

In this scenario, a boy picks up garbage from the floor, and the act of collecting garbage involves direct contact between his hand and the garbage. This contact between the boy’s hand and the garbage generates a contact force. Contact forces, as demonstrated here, occur when two objects, in this instance, the garbage and the boy’s hand, directly interact, resulting in the application of force through their physical contact.

Muscular force

Types of forces - muscular force
Lifting a courier box requires muscular force

In this scenario, a boy lifts a heavy courier box, exerting force through the use of his muscles. This specific force is referred to as muscular force. When the boy lifts the courier box, his muscles contract and exert the necessary force to overcome gravity‘s pull, allowing him to elevate the object. Muscular force, as demonstrated here, is the application of physical effort generated by muscle contractions to manipulate or move objects, such as lifting a courier box.

Friction

Types of forces - friction
Applying cement with a trowel involves friction

When applying cement with a trowel, the surfaces of the cement and the trowel come into contact and slide against each other. This interaction creates friction, which is a force that opposes the direction of the trowel’s movement. This frictional force makes it more difficult to smoothly apply the cement. Friction, in this context, is the resistance encountered when two surfaces slide or attempt to slide against each other, and it is crucial in various everyday tasks where surfaces come into contact.

Tension

Types of forces - tension
The wires of an electric tower experience tension

Tension force is a result of a pulling or stretching force that occurs in objects like ropes, cables, or wires when they are subjected to opposing forces at their ends. Electric wires hanging from an electric tower, for instance, experience forces pulling in opposite directions, creating tension within the wires. This tension force is responsible for transmitting force along the length of the wires. Tension forces are fundamental in various real-world applications, such as suspension bridges and the operation of elevators, where they play a crucial role in maintaining structural integrity and facilitating movement.

Applied force

Types of forces - applied force
Opening a refrigerator door with your hand applies an external force

In this scenario, a refrigerator door is opened by applying force with a hand. This applied force, originating from external action, induces motion in the refrigerator door. Applied forces, as exemplified here, are external influences applied to objects, like human effort, resulting in changes in the object’s state of motion or position.

Normal force

Types of forces - normal force
A brick resting on a horizontal surface experiences normal force

When an object, such as a brick, rests on a surface, there is a force exerted by the surface that acts vertically upward on the object. This force is known as the normal force. It arises due to the contact between the object and the supporting surface and serves to counterbalance the force of gravity pulling the object downward. Essentially, the normal force prevents the object from penetrating or sinking into the surface, ensuring its equilibrium.

Drag

Types of forces - drag
When a feather is dropped on the ground, it encounters drag

As a feather descends toward the ground, it encounters an upward force known as drag. In this specific example, drag signifies the resistance exerted by the air as the feather traverses through it. While the feather descends, the drag force opposes its downward movement, gradually decelerating its fall until it reaches a state of equilibrium where the drag force equals the force of gravity acting upon it. This example effectively demonstrates how drag, or air resistance, hinders the motion of objects navigating through a fluid medium like air, influencing both their speed and trajectory.

Mechanical force

Types of forces - mechanical force
A robotic arm used in a factory operates using mechanical force

A robotic arm in a factory is utilized to perform various tasks by exerting force. This force, referred to as mechanical force, is generated by the machine itself to accomplish specific functions. Mechanical forces originate from machinery or mechanical systems applying force to manipulate objects or carry out work, as demonstrated by the actions of the robotic arm in this instance.

Spring force

Types of forces - spring force
Springs in a punch hole rely on spring force

When a hole punch is pressed, it compresses an internal spring, generating a force. This spring force drives the punch’s cutting edge through the paper, creating a hole. In this example, the spring force illustrates how a compressed spring exerts pressure, allowing the hole punch to pierce the paper effectively.

Non-contact force

Types of forces - non-contact force
The falling tree branch exemplifies non-contact force

When tree branches fall to the ground, there is no direct contact between the branches and the ground. Instead, the branches descend naturally due to the force of gravity but without physical contact. This absence of contact between the two objects, the branches and the ground, exemplifies a non-contact force. Non-contact forces act on objects without requiring physical touch or direct interaction between them, as demonstrated by the gravitational force in this scenario.

Magnetic force

Types of forces - magnetic force
A magnetic sticker adheres to the refrigerator door through magnetic force

Magnetic stickers adhere to the refrigerator door due to the magnetic force. When these stickers are brought near the door, they experience an attractive force drawing them towards it. This magnetic force is responsible for the stickers sticking to the door, as it acts to pull them into contact with the door’s surface.

Gravity

Types of forces - gravity
When a mobile slips from your hand, gravity pulls it downward

Imagine a scenario where a mobile phone slips from a hand. In this situation, the force of gravity comes into play, causing the mobile to be attracted downward. Gravity is the natural force responsible for this, acting without the need for physical contact, and it consistently pulls objects towards the center of the Earth.

Electrostatic force

Types of forces - electrostatic force
Plastic wrap adheres to cloth due to electrostatic force

When a piece of plastic wrap is brought near a cloth, they exhibit a peculiar behavior – they stick together. This intriguing force, known as electrostatic force, is responsible for this interaction. Unlike contact forces, electrostatic force operates without any direct physical contact between the objects involved. In this scenario, it arises due to the buildup of electrical charges on the plastic wrap and cloth, leading to their attraction and causing them to adhere to each other.

Related

More topics

External links

Deep

Forceinphysics.com was founded by Deep Rana, who is a mechanical engineer by profession and a blogger by passion. He has a good conceptual knowledge on different educational topics and he provides the same on this website. He loves to learn something new everyday and believes that the best utilization of free time is developing a new skill.

Leave a Comment