Vertical project motion comprehensive notes

VERTICAL PROJECTILE MOTION

Free Fall
 Movement downwards due to the force of gravity only
 Acceleration due to gravity = 9,8 m.s-2 down (always applies in
free fall)

Freely falling objects
 Down +
 Acceleration ≠ 0
 Velocity = 0 at max height
 Displacement = 0 if object returns to same height
 Speed and displacement are symmetrical
 Time symmetryan object will take the same time to reach its
highest point from projection as the time taken to fall back from the
highest point to point of projection

Air Resistance
 Negligible at low speed
 Non- conservative force (do not store energy)
 Dissipative force
 Depends on velocity/ speed and surface area

Terminal Velocity
 The constant velocity that a freely falling object eventually reaches
when air resistance prevents further acceleration (air resistance =
gravity)

Equations of Motion
 Vf= Vi+at
 y= Vit+12at2
 Vf2=Vi2+2ay
 y=(Vi+ Vf2)t
 Always tabulate & state sign convention
 When an object is dropped from a moving “vehicle”, the Vi= the
velocity it had inside the moving “vehicle”

Displacement vs Time Graphs
 Displacement is the change in position
 Gradient of graph = velocity
∴
 Constant velocitystraight line graph
 Changing velocitycurved graph