Transcript V. Nonlinear Motion - x10Hosting

Ch. 3 & 4
Motion & Forces
V. Nonlinear Motion
Projectile Motion
 Circular Motion
 Free-fall

A. Projectile Motion

Projectile
 any object thrown
in the air
 acted upon only
by gravity
 follows a
parabolic path
called a trajectory
 has horizontal and vertical velocities
PROJECTILE MINI-LAB
A. Projectile Motion

Projectile Velocities

Horizontal and vertical velocities are
independent of each other!
A. Projectile Motion

Horizontal Velocity
 depends on inertia
 remains constant

Vertical Velocity
 depends on gravity
 accelerates
downward at
9.8 m/s2
ConcepTest


A moving truck launches a ball vertically
(relative to the truck). If the truck maintains a
constant horizontal velocity after the launch,
where will the ball land (ignore air resistance)?
A) In front of the truck
B) Behind the truck
C) In the truck
C) In the truck. The
horizontal velocity of the
ball remains constant
and is unaffected by its
vertical motion.
Animation from “Multimedia Physics Studios.”
B. Circular Motion

Centripetal Acceleration
 acceleration toward the center of a
circular path
 caused by centripetal force
B-BALL DEMO
PLATE DEMO
B. Circular Motion

On the ground...
 friction provides centripetal force
B. Circular Motion

In orbit...
 gravity provides centripetal force
ROUND LAB
B. Circular Motion

In orbit...
 Which satellites travel faster?
Near-Earth Satellites
Geostationary Satellites
B. Circular Motion

Extra Credit
 Use the NASA Liftoff
web site to find the
International Space
Station (“STATION”)
in the sky this weekend.
 liftoff.msfc.nasa.gov/realtime/Jpass/20/
 Write a brief description of your sighting time, appearance, & other observations.
C. Free-Fall

Free-Fall
 when an object is influenced only
by the force of gravity

Weightlessness
 sensation produced when an object
and its surroundings are in free-fall
 object is not weightless!
CUP DEMO
C. Free-Fall

Weightlessness
 surroundings are falling at the same
rate so they don’t exert a force on
the object
Go to Space Settlement Video Library.
C. Free-Fall
Space Shuttle Missions
Go to CNN.com.
Go to NASA.
NASA’s KC-135 - “The Vomit Comet”
ConcepTest 1
TRUE or FALSE:
An astronaut on the Space Shuttle
feels weightless because there is no
gravity in space.
FALSE!
There is gravity which is causing the
Shuttle to free-fall towards the Earth.
She feels weightless because she’s
free-falling at the same rate.
ConcepTest 2
Describe the path of a marble as it
leaves the spiral tube shown below.
It will travel in a straight line since the
tube is no longer exerting a net force
on it.