1. Section 1 Laws of Motion p. 346
Chapter 11 Forces
Section 1
Laws of Motion
p. 346

2. Observe effects of 1st two laws of motion
Objectives
Observe effects of 1st two laws of motion
Calculate the gravitational pull of an object and its altitude based on falling time

3. I. Newton’s First Law - Inertia
A. Inertia- tendency for an object in motion to stay in motion and an object at rest to stay at rest unless acted upon by some outside unbalanced force
B. Inertia is directly related to mass
II. Newton’s Second Law
A. Force is equal to mass times
acceleration F=ma
B. Measured in Newtons =
1 kg x 1 m/s2 = 1 N

4. Chapter 11 Forces
Section 2
Gravity
p. 352

5. I. Universal Gravitation Equation
F= G(m1m2/d2)
A. All matter is affected and exerts
gravity A Gravity Demonstration
B. Gravity increases as mass increases
C. Gravity decreases as distance
increases Blue Angels
II. Free Fall and Weight Weightlessness
Free fall- when gravity is the only force
acting on an object
A. Gravitational acceleration constant
on Earth is 9.8 m/s2 = g

6. B. Weight equals mass times free fall
acceleration
1. Weight = mass x free-fall
acceleration or w=mg
2. In space, you appear weightless
because everything is
accelerating (falling) at the same
rate (apparent weightlessness)
C. Weight and mass are different
(moon = g = 1.6 m/s2)
Galileo’s Laws of Falling Bodies (p27)
Feather & Hammer Drop

7. D. Weight influences shape
E. Velocity is constant when air
resistance balances
Terminal Velocity- no longer
accelerating because gravity is
balanced by air resistance
F. Orbiting- combination of free fall and
forward motion
III. Projectile Motion- curved path of an object with force applied behind it on or near gravity (e.g.- orbit)
One motion does not affect the other