Transcript Newton`s Second Law Pages 46-48

Newton’s Second Law
Pages 46-48
Describe your acceleration if you are in
a circular motion. What is the net
force of your motion?
• You are constantly accelerating; the net force
is equal to zero.
When an object moves is a circular
motion, the net force on the object
is called centripetal force.
Explain how a satellite stays in orbit
around the Earth.
• The Earth’s gravity pulls the satellite towards
the Earth. The satellite’s speed (29,000 km/h
or 18,000 mph) allows it to move fast enough
to fall with a curve equal to the Earth’s curve.
• F-16 Plane = 1,500 mph
• Bullet = 2,000 mph
What is air resistance?
• A form of friction.
The air resistance on an object
depends on two things. What are
they?
1. The shape of the object.
1. The speed of the object.
What is the center of mass?
• Point in an object that moves as if all of the
object’s mass were concentrated at that point.
Newton’s Second Law Equations:
Acceleration = Net Force ÷ Mass
Net Force = Mass x Acceleration
Mass = Net Force ÷ Acceleration
Units of Measurement:
Force  N
Acceleration  m/s2
Mass  kg
Page 48: Self Check, questions
2,4,5,6, and 7
2. The force of the Earth’s gravity will decrease
so your weight will decrease.
4. The net force is pushing diagonally on the car
and to the right.
5. When their forces are unbalanced.
6. 1,500 kg × 2 m/s2 = 3,000 N
7. 300 N ÷ 1,500 m/s2 = .2 kg