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Chapters 7 & 8: Gravity
Plan
1.
Free Fall and Projectiles
2.
The Universal Law of Gravitation
3.
Gravitational Constant and Free-Fall Acceleration
4.
Examples
5.
Ocean Tides
5.
Summary
Chapter 7: Homework
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Review Questions: 4, 5, 8, 9, 10,11, 19
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Exercises: 2, 6, 19
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Problems: 2, 3, 4
Chapter 8: Homework
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Review Questions:1, 2, 4, 8
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Exercises: 3, 8, 16, 20
1. Free Fall and Projectiles
Definition:
A projectile is an object that moves
under the influence of gravity.
Examples: a tossed stone, a cannonball, a
bullet, a ball,…,an athlete,
a satellite, a
spaceship,
the moon, etc.
The curve path of a projectile
Example 1:
Horizontally tossed stone
The curve is the result of composite
motion in two directions -
horizontal
and vertical
This curve is called a parabola!
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X
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