Physics Sem 1 Exam Review

Physics

Branch of science that involves the study of the physical world: energy, matter and how they are related.

Position

The distance and direction from the origin to an object

Displacement

the change in position of an object

vector

A quantity that has magnitude and direction

scalar

A quantity that has only magnitude

velocity

the ratio of an object's change in position to the time interval during which the change occurred.

speed

the absolute value of an object's velocity

nonuniform motion

Motion where velocity is changing.

Acceleration

The rate at which velocity changes

free fall

the motion of a falling object when the only force acting on it is gravity

Force

A push or a pull

system

object or objects of interest that can interact with each other and the external world

external world

objects that interact with the system

contact force

when an object from the external world touches a system and exerts force on it

field force

a force that is exerted without contact

net force

The sum of all forces acting on an object

Newton's Second Law

The acceleration of an object is directly proportional to the net force acting on the object, is in the direction of the net force, and is inversely proportional to the mass of the object.

Newton's First Law

An object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force.

Inertia

The tendency of an object to resist a change in motion

weight

the gravitational force exerted on an object

Apparent Weight

The support force acting on an object

Weightlessness

the condition where there are no contact forces acting to support the object and the object's apparent weight is zero.

Drag force

the force exerted by a fluid on the object moving through the fluid

Newton's Third Law

All forces come in pairs that are equal in magnitude and opposite in direction

Tension

The force exerted by a string, rope, cable, etc.

Normal Force

the perpendicular contact force exerted by a surface on another object