The Ordered Universe

Created by Dr Adele Register

Physical Events



Without the predictability of physical events the scientific method could not proceed.


Stonehenge pic

A Giant Calendar

Built to Keep Track of Time

Began in 2800 BC, Still Accurate Today

As seen by:

Ptolemy – 2nd century

Copernicus - 16th century

Brahe – late 16th century

Kepler – early 17th century

Galileo – early 17th century


Galileo pic

“The Father of Experimental Science”


collecting data using instruments and mathematical calculations


Speed = distance/time

Velocity – speed in a specific direction

Acceleration – rate of change in velocity

Newton’s Laws of Motion

1st Law

a moving object will continue moving in a straight line at a constant speed, and a stationary object will remain at rest, unless acted upon by an unbalanced force

Newton’s Laws of Motion

2nd Law

the acceleration produced on a body by a force is proportional to the magnitude of the force and inversely proportional to the mass of the object

Newton’s Laws of Motion

3rd Law

for every action there is an equal and opposite reaction

Gravity = our #1 force

“an attractive force between any 2 objects in the universe which is proportional to the masses of the objects and inversely proportional to the square of the distance between them”


force of gravity on an object in a particular place can change



amount of actual matter an object has stays constant


“G” – universal constant, applies to any 2 masses in the universe

“g” – gravity on the Earth’s surface only


If we drop two objects from the same distance above the surface of the Earth, which will fall faster, the heavier object or the lighter object?