Force Push and Pull

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What is Force?

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A force is defined as the application of push or pull on an object with a mass in such a way that it will affect the motion of an object when unopposed. It can cause an object to move from its state of rest, i.e., change its velocity (to accelerate) or can change its direction of movement. It is an interaction that causes or changes the motion of an object. When a force is applied, it has both magnitude and direction. Hence, it is a vector quantity. 

It is denoted by the symbol F and its S.I. unit is Newton (N). The other units of force are dyne, poundal, pound-force, kip, etc. 

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What is a Push Force? 

Push is defined as a force that causes an object to move from its state of rest. When an object is pushed, it tends to move away. Kicking a ball, closing a door, pushing a trolley, inserting a plug into the socket are all examples of push force.  

What is a Pull Force?

The pull is defined as a force that causes an object to move towards the person who is pulling the object. Opening a door, plucking the string of a guitar, drawing a bucket of water from the well, pulling the curtain are all examples of pull force. 

Types of Forces

A force can be applied to an object in two ways, i.e., by making a contact with the object or by not making a contact with the object. Based on that, there are two types of forces. They are known as contact force and non-contact force. 

Contact Force

A contact force is defined as a force that requires a contact to apply a force on an object. Kicking a ball, closing a door are all examples of contact forces because contact is made in each case. It is further classified into three forces, namely, Frictional force, Applied force, and Normal force.

  • Frictional Force: When a ball is softly kicked, it rolls over the floor. At that time, a force acts opposite to the direction of the moving ball which eventually stops the ball. This type of force is called frictional force. Generally, it resists the motion of the object when the surface of an object comes in contact with the surface of another object.

  • Applied Force: When a person or an object applies force on another object, which results in the movement of the object. It is called an applied force.

  • Normal Force: When an object is resting upon a surface, the surface exerts an upward force to balance the force exerted by the weight of the object. The upward force is known as the normal force which is applied by the surface. 

Non-Contact Force 

Non-contact force is defined as a force that is exerted without making any contact. It is further classified into three forces. They are Gravitational force and Magnetic force. 

  • Gravitational Force: The attraction between any two objects with mass is known as gravitational force. It is a natural phenomenon. Stars, planets, galaxies have an attractive force acting between them all the time. On Earth, physical objects possess weight due to gravity and the ocean tides occur due to the moon's gravity.

  • Magnetic Force: A magnetic force is defined as a force exerted between two poles of a magnet and also between electrically charged moving particles. It can be either attractive or repulsive.  

Did You Know?

It is assumed often that if an object is at rest, no force is acting on it. But, this is not true. When an object is at rest, there are two forces which act simultaneously on it. One is the gravitational force which acts downwards and the other one is Normal force which acts upwards. These two forces balance each other. Hence, the net force acting on the ball is zero. Now, if the ball is kicked, then only it will move from its stationary position because an external force greater than the other two forces is applied to it now. Hence, it will move in a particular direction. 

FAQ (Frequently Asked Questions)

1. What Are the Effects of Force?

A force can have different effects on an object. It can make a stationary object move (i.e., change its velocity or accelerate it) and can stop a moving object or slow down its speed (i.e., decelerate it). The direction of a moving object can be changed by applying a force. For example, during a football match, a football player kicks the ball in a certain direction and the opponent player kicks the balls in the opposite direction towards their goal. Hence, the opponent player is applying a force towards the opposite direction of the moving ball. Therefore, the direction of the ball is changed due to the application of force. The shape and size of an object can also be changed with the application of force.

2. What Is Centripetal and Centrifugal Force? Give Some Examples.

When an object is in curvilinear motion, two types of forces act on it. One is centripetal force and the other one is centrifugal force. A centripetal force is defined as a force that acts towards the center or the axis of rotation when an object moves in curvilinear motion. Planets revolving around the sun, turning a car are examples of centripetal force. A centrifugal force is defined as a force that acts away from the center, i.e., it acts outward when an object moves in a circular motion. Mud flying off of a tire, a bike making a turn are examples of centrifugal force.