31 terms

Speed

Distance travelled in a given time

Displacement

Distance in a given direction

Velocity

Speed in a given direction

Acceleration

Rate of change of velocity with respect to time

Vector

A quantity that has both magnitude and direction in space

Scalar

A quantity that has magnitude in space only and no direction

Force

Mass x Acceleration

Mass

The measure of how difficult it is to accelerate a body

Weight

Mass x Gravity

Momentum

Mass x Velocity

Newton's First Law

States that every body will remain in a state of rest or travelling with a constant velocity unless an unbalanced external force acts on it

Newton's Second Law

States that when an unbalanced force acts on a body the rate of change of the body's momentum is directly proportional to the force and takes in the direction of the force

Newton's Third Law

States that is a body A exerts a force on a body B, then body B exerts an equal but opposite force on body A.

Friction

A force that opposes motion

Principle of Conservation of Momentum

States that in any interaction between two or more bodies the total momentum of the bodies before the interaction is equal to the total momentum after the interaction provided no external forces act on the system of bodies

Density

Mass per unit Volume

Pressure

Force per unit Area

Archimedes' Principle

States that when an object is partially or completely immersed in a fluid it experiences an upthrust equal in magnitude to the weight of the fluid displaced

The Law of Flotation

States that the weight of a floating body is equal to the weight of the fluid it displaces

Boyle's Law

States that at a constant temperature the volume of a fixed mass of gas is inversely proportional to its pressure

Newton's Law of Universal Gravitation

States that any two point masses in the universe attract each other with a force that is directly proportional to the product of their masses and inversely proportional to the square of the distance between them

Moment

Force X Perpendicular Distance

Laws of Co-planar Forces

When a system is in a state of equilibrium:

1. The vector sum of the forces in any direction is zero

2. The sum of the moments about any point is zero

1. The vector sum of the forces in any direction is zero

2. The sum of the moments about any point is zero

Couple

Two parallel forces with the same magnitude acting in opposite directions

Torque

Force X Perpendicular Distance

Work

Force X Displacement

Energy

The ability to do work

Principle of Conservation of Energy

States that energy cannot be created or destroyed but can only be converted from one form to another

Kinetic Energy

The energy a body has due to its motion

Potential Energy

The energy a body has due to its position in a force field

Power

Rate at which work is done

or

Rate at which energy is converted from one form to another

or

Rate at which energy is converted from one form to another