1. Photo Album by Robert MacKay

2. The Movers in Physics Aristotle 384-322 BC Copernicus 1473-1543 (De Revolutionibus) Galileo (1564-1642) Newton (1642-1727) Einstein (1879-1955)

9. Law of inertia (Newtons1st 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

21. 200 N 800 N ? N

22. 200 N 800 N 500 N

23. Same painter and plank (800N and 200N) ? N

24. Same painter and plank (800N and 200N) 830 N

25. Same painter and plank (800N and 200N) ? N

26. Same painter and plank (800N and 200N) 100 N

30. 150 N

32. 450 N

34. 800 N 400 N