1. Proj. Motion guidelines
horiz. & vert. motion are considered SEPARATELY
horiz motion: not affected by acceleration
vert motion: affected by acceleration due to gravity (-9.8 m/s2)
Air resistance is ignored
tup = tdown (only when take-off and landing height are the same)
Vv at apex = 0

2. What is the stuntman's velocity, displacement, and acceleration while falling. Given: times at 1,2,3 sec
Horizontal motion
dh= vh (t)
Vertical motion
vf = vi + at
vf2 = vi2 + 2ad
d = vit + (1/2)at2
Time velocity displacement acceleration
0 s
1 s
2 s
3 s
-9.8 m/s
-4.9 m
-9.8 m/s2
-9.8 m/s2
d = vit + (1/2)at2
vf = vi + at
d =
o + (1/2) (-9.8 m/s2) (1s)2
vf =
o + (-9.8 m/s2) (1s)
d =
-4.9 m
vf =
-9.8 m/s

3. What is the stuntman's velocity displacement and acceleration while falling at seconds 0-3?
Horizontal motion
dh= vh (t)
Vertical motion
vf = vi + at
vf2 = vi2 + 2ad
d = vit + (1/2)at2
Time velocity displacement acceleration
0 s
1 s
2 s
3 s
-9.8 m/s
-4.9 m
-9.8 m/s2
-9.8 m/s2
-19.6 m
-19.6 m/s
-29.4 m/s
-44.1 m
d = vit + (1/2)at2
vf = vi + at
d =
o + (1/2) (-9.8 m/s2) (1s)2
vf =
o + (-9.8 m/s2) (1s)
d =
-4.9 m
vf =
-9.8 m/s

4. Bungee jumping Skippers Canyon, NZ

5. Bungee jumping Skippers Canyon, NZ

6. What was the vertical velocity at the instant the bungee began to lengthen?
Given:
-102 meter drop
Vi = -3.0 m/s
Horizontal motion
dh= vh (t)
Vertical motion
vf = vi + at
vf2 = vi2 + 2ad
d = vit + (1/2)at2
vf2 = vi2 + 2ad
vf2 = (-9.8)(-102)
vf2 =
vf = m/s

7. .
Trampolinist goes up.. What is the time to peak and how high did they jump?
Given:
Vi = 10.5 m/s
Horizontal motion
dh= vh (t)
Vertical motion
vf = vi + at
vf2 = vi2 + 2ad
d = vit + (1/2)at2
d = vit + (1/2)at2
vf = vi + at
d =
(5.0 m/s) (.51 s) + (1/2) (-9.8 m/s2) (.51s)2
0 =
5.0 m/s + (-9.8 m/s2) (t)
-5.0 m/s
-9.8 m/s2
= 0.51 s
d =
1.28 m

8. Long jumper: How high and how far did they go?
Step 1: resolve net velocity
9.8 m/s
cos 23.2° * 9.8m/s
vh = 9.01 m/s
Sin 23.2° * 9.8m/s
vv = 3.86 m/s
23.2°
Given:
tup = tdn
Step 3: dv
Step 2: tup
dv = vit + (1/2)at2
dv=
(3.86 m/s) (.394 s) + (1/2) (-9.8 m/s2) (.394 s)2
vf = vi + at
vf = 3.86 m/s + (-9.8 m/s2) (tup)
dv= .76 m
-3.86 m/s
-9.8 m/s2
= .394 s

9. Long jumper: How high and how far did they go?
Step 4: total time
9.8 m/s
tup = tdn
23.2°
Given:
tup = tdn
.394 s s = .788 s
Step 5: dh
dh= vh (t)
Dh = 7.10 m
(9.01 m/s) (.788 s) =