Transcript Projectile Fact 1

Bellwork 2-27-12
What is the acceleration
due to gravity on earth?
9.8 m/s²
Important Projectile
Information
Projectile
Any object that moves through the air, with
only the force of gravity acting upon it.
Trajectory
The path that a projectile moves along
through the air is called its trajectory.
Projectile Fact 1
An object in a trajectory can be considered
to have two different velocities, a vertical
velocity and horizontal velocity.
Projectile Fact 2
The acceleration
of a projectile is
always 9.8 m/s².
Projectile Fact 3
As an object rises in its trajectory, its
vertical velocity decreases by 9.8 m/s
each second.
Projectile Fact 4
As an object falls in its trajectory, its
vertical velocity increases by 9.8 m/s
each second.
Projectile Fact 5
At the very top of its trajectory, an
object’s vertical velocity is zero.
Projectile Fact 6
Assuming no air resistance, the
horizontal velocity of an object in its
trajectory never changes.
Projectile Fact 7
A projectile will have the same speed in
the same positions when it rises and
when comes back down.
Same Position
Same Speed
COMPONENTS
OF A
PROJECTILE
Forces
Acceleration
Velocity
Horizontal
Velocity (Vx)
Vertical
Velocity (Vy)
None
Yes
gravity pulls
it downward
Yes
a=9.8 m/s²
None
Constant
stays the same
Changing by
9.8 m/s each
second