Kinematics
1. predictive power
2. important tool
3. solve nature’s puzzle
Galileo Galilei:object fall at constant speed
Aristotle vs Galileo: objects gain speed as they fall
A mass dropped from greater height leaves greater impact
Feathers do fall at constant speed
Air slows objects down! … too fast
Position, Velocity
Velocity: v = Δx / Δt
Acceleration a = ΔV / Δt
v = 5m / 1s = 5 m/s
Average deviation
2.00m, 1.20m, 2.80m -> 1.6/3 => 0.53
1.97m, 1.98m, 1.97m -> 0.02/3 => 0.0067
m / s / s
“constant acceleration means an object gains equal speed during equal time intervals”
Vαt^2
x = t^2, a = 10m/s^2 = g
V0 = 10m/s
