Force is something that we come across in everyday life.
It can be defined as an external cause or energy that results in movement or a change in position of a body that is either at rest or moving in a straight line.
It is an external push or pull that acts on an object. Force can be used to cause an object to begin moving or to change direction.
When an object pushes or pulls another object, it is said to be applying force on that object.
Applied force is, therefore, the force that is applied by one object to another to cause the object to change its state of rest, its direction of motion, or its size or shape.
Characteristics of Applied Force
Applied force has the following characteristics:
- It is the result of the interaction between at least two different objects.
- It is a vector quantity i.e. it has both magnitude and direction.
- It results in a change in an object’s state of rest, motion, direction, shape or size.
Examples of Applied Force in Real Life
The following are some examples of applied force in real life.
1. Pressing a switch to turn a light on or off
When you walk into a dark room, the first thing you do is search for the light switch and press it to turn the light on.
You press the light switch when you leave the room to turn the light off.
When you press the switch, it moves down or up to turn the light on or off. You apply force to the switch to move it down or up.
This is an example of applied force used to change the position of an object.
2. Kicking a ball
Soccer is a fun game. It involves kicking a ball in an effort to get it into a goal.
The act of kicking the ball results in the ball moving. Players also kick the ball to cause it to change direction.
Kicking is therefore an example of using applied force to change the state of rest of an object as well as to change its direction.
3. Riding a bicycle
When you are first learning to ride a bicycle, you learn to push on the pedals one at a time.
Riding a bicycle involves applying force to the pedals of the bicycle to rotate them.
The applied force is used to change the state of rest of the pedals and cause them to go into motion (i.e. to rotate).
4. Lifting a book
A book on a table is said to be in a state of rest. When you pick the book up, you are applying a force to the book to change its state of rest.
The act of picking the book up causes it to move from one position to another.
You are applying force to the book to change its state or rest.
5. Molding clay
When creating pottery or other clay objects, the artisan presses on the clay to manipulate its shape until it forms the desired shape.
The artisan is applying force to the clay to change its shape and mold it into the final product.
This is an example of applied force being used to change the shape of an object.
6. Crushing a can of soda
Crushing a can of soda after emptying its contents is something many people like to do to save space when disposing of these cans.
The act of crushing the can involves applying force to the can to change its shape and size.
7. Opening or closing a door
Opening and closing doors is something we do daily without a second thought.
We apply force to the doorknob to turn it and open the door.
We also apply force the door handle to push the door open or shut.
Opening and closing doors use applied force to change the state of rest of the door.
8. Pushing a box on a floor
The easiest way to move a heavy box across a room is to push it across the floor.
In order for the box to move, you must apply force to one side of the box.
The box moves in the direction in which the force is applied.
Applied force is used here to change the state of rest of an object.
9. Pushing earth with a bulldozer
Bulldozers are used to clear the ground and remove dirt in the early stages of construction.
The bucket of the bulldozer is used to move the dirt.
Force is applied by the bulldozer to the dirt to change its state of rest.
10. Checking your weight on a scale
Are you on a weight loss journey? Do you feel like you’ve lost or put on more than a few pounds?
When you hop on the scale to check your weight, you’re actually measuring applied force.
There is a spring inside a mechanical weighing scale. When you step on the scale, your body applies force to the spring to compress it.
The shortening in the length of the spring is measured and this gives an indication of the amount of force applied which is read as weight.
Applied force is any external force acting on an object by another object.
We use applied force to move objects, change their positions or their sizes or shapes.
This is the most common type of force we encounter every day and is vital for many of the tasks we carry out.