Photo Album

by Robert MacKay

The Movers in Physics

• Aristotle 384-322 BC

• Copernicus 1473-1543 (De Revolutionibus)

• Galileo (1564-1642)

• Newton (1642-1727)

• Einstein (1879-1955)

Law of inertia (Newton’s1st Law)

• Every object continues in its state of rest, or of uniform motion in a straight line, unless it is compelled to change that state by forces impressed upon it.

• acceleration = 0.0 unless the objected is acted on by unbalanced forces

200 N

800 N

? N

200 N

800 N

500 N

Same painter and plank (800N and 200N)

? N

Same painter and plank (800N and 200N)

830 N

Same painter and plank (800N and 200N)

? N

Same painter and plank (800N and 200N)

100 N

150 N

450 N

800 N 800 N

800 N400 N400 N