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Physics 130 1
Motion in Two Dimensions (Ch 4)
•All projectiles
follow a parabolic
path in the
absence of air
resistance.
Physics 130 2
Projectile Demo
•Summary:
•both balls hit the table
at the same time
•initial horizontal motion
of yellow ball does not
affect its vertical motion
Physics 130 3
ConcepTest
•In the projectile motion demo, which ball has
the largest velocity just before hitting the
table?
a) the ball the drops straight down
b) the ball that travels horizontally while it
drops
c) they both have the same velocity
d) impossible to determine unless we know
the initial horizontal velocity
Physics 130 4
Two Dimensional Motion
•Horizontal and Vertical
motions are
independent.
•We can solve them
independently.
•Y-motion
•free-fall motion
•a = g
•determines time-of-flight
•X-motion
•constant-velocity motion
•determines range
