projectile motion down
DESCRIPTION
A ball in free fall as it moves downwardTRANSCRIPT
Projectile motion
A ball falls freely downward
Gravitational force
m M
Ball pulls Earth
Earth pulls ball
Weight
Time of fall (s) Velocity (m•s-1) down
0 0
1 10
2 20
3 30
4 40
5 50
Time of fall (s) Velocity (m•s-1) down
0 0
1 10
2 20
3 30
4 40
5 50
+1 s +10 m•s-1
Time of fall (s) Velocity (m•s-1) down
0 0
1 10
2 20
3 30
4 40
5 50
+1 s +10 m•s-1
Time of fall (s) Velocity (m•s-1) down
0 0
1 10
2 20
3 30
4 40
5 50
+1 s +10 m•s-1
Time of fall (s) Velocity (m•s-1) down
0 0
1 10
2 20
3 30
4 40
5 50
+1 s +10 m•s-1
Time of fall (s) Velocity (m•s-1) down
0 0
1 10
2 20
3 30
4 40
5 50+1 s +10 m•s-1
𝒄𝒉𝒂𝒏𝒈𝒆𝒊𝒏𝒗𝒆𝒍𝒐𝒄𝒊𝒕𝒚𝒕𝒊𝒎𝒆
=
= = 10 m•s-2 down
= - 10 m•s-2
Actually:
Acceleration due to gravity, g = - 9,8 m•s-2
Weight
Acceleration due to gravity, g = 9,8 m•s-2
downward
x
y
y
up: +
down: -
If down is negative:
g = 9,8 m•s-2 downward = - 9,8 m•s-2
Time of fall (s) Velocity (m•s-1) down
0 0
1 9,8
2 19,6
3 29,4
4 39,2
5 49
Time of fall (s) Velocity (m•s-1) down
0 0
1 9,8
2 19,6
3 29,4
4 39,2
5 49
+1 s +9,8 m•s-1
Time of fall (s) Velocity (m•s-1) down
0 0
1 9,8
2 19,6
3 29,4
4 39,2
5 49
+1 s +9,8 m•s-1
Time of fall (s) Velocity (m•s-1) down
0 0
1 9,8
2 19,6
3 29,4
4 39,2
5 49
+1 s +9,8 m•s-1
Time of fall (s) Velocity (m•s-1) down
0 0
1 9,8
2 19,6
3 29,4
4 39,2
5 49
+1 s +9,8 m•s-1
Time of fall (s) Velocity (m•s-1) down
0 0
1 9,8
2 19,6
3 29,4
4 39,2
5 49+1 s +9,8 m•s-1
𝒄𝒉𝒂𝒏𝒈𝒆𝒊𝒏𝒗𝒆𝒍𝒐𝒄𝒊𝒕𝒚𝒕𝒊𝒎𝒆
=
= = 9,8 m•s-2 down
= - 9,8 m•s-2
Time of fall (s) Velocity (m•s-1) down
0 0
1 9,8
2 19,6
3 29,4
4 39,2
5 49
Time of fall (s) Velocity (m•s-1)
0 0
1 - 9,8
2 - 19,6
3 - 29,4
4 - 39,2
5 - 49
0 1 2 3 4 5 6
-60
-50
-40
-30
-20
-10
0
Time (s)
Velo
city
(m•s
-1)
Time of fall (s) Acceleration (m•s-2) down
0 - 9,8
1 - 9,8
2 - 9,8
3 - 9,8
4 - 9,8
5 - 9,8
Time of fall (s) Acceleration (m•s-2)
0 - 9,8
1 - 9,8
2 - 9,8
3 - 9,8
4 - 9,8
5 - 9,8
0 1 2 3 4 5 6
-12
-10
-8
-6
-4
-2
0
Time (s)
Acce
lera
tion
(m•s
-2)
Time of fall (s) Position (m) (below start)
0 0
1 4,9
2 19,6
3 44,1
4 122,5
5 240,1
Time of fall (s) Position (m)
0 0
1 -4,9
2 -19,6
3 -44,1
4 -122,5
5 -240,1
0 1 2 3 4 5 6
-300
-250
-200
-150
-100
-50
0
Time (s)
Posi
tion
(m)
Weight
Air resistance
Weight
Air resistance
Free fall
Weight
Air resistance
g
Weight
Air resistance(negligible)
Weight
Weight
Free fall
Weight
g
Vacuum tube
Falling in vacuum tube
WeightWeight
Falling in vacuum tube
WeightWeight
Free fall
Falling in vacuum tube
WeightWeight
g
Movie: Falling in vacuum tube
http://www.phys.vt.edu/~demo/images/Mechanics/M32b.jpg