The Definition Of Force and Pressure ?

Force and Pressure

Introduction

• When an object is either pushed or either pulled is known as a Force.

• Motion, generated in an object, is because of an action of a force.

• The applied force makes the table move in a given direction.

•  The strength of a force is commonly Known by the magnitude.

•  Force also has Direction,  if the magnitude or direction changes, it directly affects the force.

•  If the force is applied in the opposite direction, the direction of motion, then it results in a decrease speed of the object.

•  If an object is in motion, then external force may change in the state or direction of motion of that object.

• The state of motion of an object is expressed by its speed and the direction of motion.

•  The state of 'Rest’ of an object is considered to be the zero speed.

•  An object cannot move by itself.

• Any object cannot change its speed by itself.

• An object cannot change its direction by itself.

• Any object cannot change by itself.

• A force can make an object move from rest.

• A force can change the speed of a moving object.

• A force can change the direction of a moving object.

• A force can change the shape of the object.

• The force caused by the action of any muscles is known as the muscular force.

• Some force decreases the speed of a moving object, known as ‘friction.’ e.g. Moving the wheel on the road; once the source of the force stops working then wheel stops because of friction.

• The force applied by a charged body on another charged or uncharged body is known as ‘electrostatic force.

• Objects or things that fall towards the earth, as earth pulls it towards itself; this force is known as the force of gravity or gravity.

• The force of gravity is applicable to all objects. In fact, every object in this universe, irrespective of its size and shape, exerts some force on every other object. It happens only because of the ‘gravitational force.’

• This envelope of air is known as the atmosphere that extends up to many kilometres above the surface of the earth.

• The pressure exerted by the air is known as atmospheric pressure.

• The pressure inside our bodies is exactly equal to the atmospheric pressure and annuls the pressure acting from outside
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• see the image given below.
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• * Liquids and gases also exert pressure on the walls of their respective containers.