1. Ballistic Cart Slo-mo

2. Which diver hits first, the one that falls or the one that runs off the high-dive?

3. What lands first, a bullet shot horizontally or the one that is dropped?

4. Intro to Projectile Motion
V0x = 10 m/s +x +y 5m
If there was no gravity, where would the ball be at t=1 s?
10m
15m
x = x0+Voxt = = 10 m
20m
at t=2 s?
25m
x = x0+Voxt = = 20 m
30m
at t=3 s?
x = x0+Voxt = = 30 m
35m
40m
45m

5. Intro to Projectile Motion
V0x = 10 m/s +x +y
10 m/s
9.8 m/s 5m
But there IS gravity so where is the ball at t = 1 s?
10m
x = x0+Voxt = = 10 m
What is its velocity at t = 1 s?
15m
y = y0+Voyt + ½(a)t2
20m
No x acceleration
y = ½(9.8)(1)2 = 4.9 m
25m
vx = vox = 10 m/s
vy = voy + at
This is the same distance it would fall in 1 second if it is dropped.
30m
No initial y velocity
35m
vy = =
9.8 m/s
40m
45m

6. Intro to Projectile Motion
V0x = 10 m/s +x +y
10 m/s
9.8 m/s 5m
Where is the ball at t = 2 s?
10m
x = x0+Voxt = = 20 m
15m
y = y0+Voyt + ½(a)t2
10 m/s
19.6 m/s
20m
y = ½(9.8)(2)2 = 19.6 m
25m
What is its velocity at t = 2 s?
30m
vx = vox = 10 m/s
35m
vy = voy + at
40m
vy = = 19.6 m/s
45m

7. Intro to Projectile Motion
V0x = 10 m/s +x +y
10 m/s
9.8 m/s 5m
Where is the ball at t = 3 s?
x = x0+Voxt = = 30 m
10m
y = y0+Voyt + ½(a)t2
15m
y = ½(9.8)(3)2 = 44.1 m
10 m/s
19.6 m/s
20m
What is its velocity at t = 3 s?
25m
vx = vox = 10 m/s
30m
vy = voy + at
35m
vy = = 29.4 m/s
40m
10 m/s
29.4 m/s
45m

8. Intro to Projectile Motion
V0x = 10 m/s +x
What is the magnitude and direction of the velocity at t = 3 s? +y
10 m/s
9.8 m/s 5m
10 m/s
-29.4 m/s θ
10m +y
15m +x
10 m/s
19.6 m/s
20m
25m
30m
Velocity is always tangent to the parabolic path
35m
40m
10 m/s
29.4 m/s
45m

9. Vox = 7 m/s +x +y
48 m
How fast should he run to land in center of the pool?
4.8 m/s
10 m