Force and pressure

 

Force:  Is the push and pull upon an object resulting from the object's interaction with another object .whenever there is an interaction between two objects ,there is a force upon each of the objects.

• Force is a vector quantity which means it has direction
• The unit of force is Newton and is represented by capital N
• Force can be acted upon on the face, edges, side or vertices of the object
• The instrument used to measure the force is called dynamometer

Examples of forces:  A goalkeeper stopping the ball 

A hockey player pushing the ball in forward direction

A boy catching a ball to stop it

There are two major types of forces:

 Contact forces and Non-contact forces 

 Examples of contact forces are muscular forces, force of friction etc

 similarly, examples of non-contact force or magnetic force, gravitational force etc

Contact force : Is the force that is applied by object in contact with each other contact for is governed by newtons law .Contact force is responsible for most of the interactions we experience in daily life

 example:

•  lifting a book lying on a table
• Lifting a bucket of water with your hand since muscular force

Examples of contact forces 

• Muscular force 
• Mechanical force 
• Fictional force

Non-contact force 

Force that acts through spaces without making direct contact with the body are called non-contact forces 

examples of non-contact forces are

•  Gravitational force 
•  Electrostatic force 
•  Magnetic force

Pressure :Is the physical force Applied perpendicular to the surface of an object per unit area over which the force is distributed.

• The unit of pressure is Pascal and is represented by Pa
• The pressure is a scaler quantity which means it doesn't have a direction
• Pressure only acts on the surface or face of the object
• The instrument used to measure pressure is called as Manometer

The formula for Pressure is

   pressure=Force/Area

The pressure is exerted by liquid and gases both liquid and gases exert pressure on the inner wall of the container they are kept in for instance if there is a whore in the water bottle the water leak out because of the pressure exerted by water on the bottle.

Similarly gases apply pressure on the inner surface of the container.

Atmospheric pressure: The pressure exerted by the air around us is called atmospheric pressure this pressure is a result of weight of the gases in the earth atmosphere around us.