1. Sy = -40.8 m
ay = -9.81 ms-2
Reference
uy=0
Point
Find vy.
40.8 m
v = u + at
s = ut + ½ at2
v2 = u2 + 2 as
Taking upwards
as positive vy=-28.3m/s
flipperworks.com

2. Qualitative Description of Motion
Positive At A, object is first released
Velocity
Uy = 0 ms-1  no air resistance
Resultant force, Fnet is equal to the
weight W, which is the only force
acting on the object.
Acceleration = g = 9.81m/s
Weight (W =mg)
Fnet = mg
Object is accelerating. flipperworks.com

3. V / ms-1
Vt
C Qualitative Description of Motion
B
At B, object is moving downwards
A t/s
•As motion is downward, the drag
force must be upwards.
Drag Force(Fd) •Object accelerates with smaller
acceleration. acceleration, a < g
•Downward velocity still increasing
Velocity
Weight (W=mg) Fnet = mg - Fd flipperworks.com

4. V / ms-1
C
Qualitative Description of Motion
Vt
At C, object reaches terminal velocity
B
A t/s •As velocity increases, the drag force
increases as well.
•Drag force equal and opposite to the
Drag Force
weight: no resultant force
•Acceleration is zero
•Velocity stops increasing  terminal
velocity (Vt)
Velocity
(Vt) Fnet = mg – Fd = 0
Weight flipperworks.com
acceleration, a = 0