Transcript 2007_SeeS_PhysicsofMotion_Intro

SeeS
Distance
How much ground an object has
covered
Velocity
How fast an object is going in a
certain direction.
Acceleration
How quickly an object slows down or
speeds up.
Force
A push or pull that causes an object
to move, stop, or change direction.
The larger the weight, the larger the force.
The larger the force, the larger the acceleration.
Video
The Ultimate Race!
Jet Fighter vs Car vs Motorcycle
1.00
• Plane passes bike at about 20
seconds [A]
Position(mile)
Position versus Time
0.75
Car: Porsche
Jet: Jaguar
Motorcycle: Ninja
0.50
• Car passes bike at about 25
seconds [B]
• Plane needs about 2000 ft to
take off
0.25
0.00
0
5
10
Velocity (mph)
20
25
30
Time (sec)
350
300
15
Velocity versus Time
Car: Porsche
Jet: Jaguar
Motorcycle: Ninja
250
200
CAR:
top speed 200 MPH (325 km/hr or
90 m/sec).
150
100
50
0
0
5
10
MOTORCYCLE:
top speed 175 MPH (280 km/hr or
80 m/sec).
15
Time (sec)
20
25
30
JET FIGHTER:
top speed 1,400 MPH (about
MACH 2)
take off speed 200 MPH.
Jet Fighter versus Car versus Motorcycle
MOTORCYCLE: Accelerates fastest off the starting line
(because it is the lightest). But its top speed is only
about 175 MPH (280 km/hr or 80 m/sec).
CAR: Accelerates second fastest off the starting line
(because it is the next lightest).
But top speed is only about 200 MPH (325 km/hr or 90
m/sec).
JET FIGHTER: Slowest of the starting line (it is by far the
heaviest). But is accelerates for the longest time - 0.6
g for more than 25 seconds.
But top speed MACH 2 or 1,400 MPH with a take off
speed of about 200-250 MPH.
Sprinter 100 m Split Times
World Record & Grade 5s
100
90
Position (meter)
• Sprinters accelerate fairly quickly
(2 to 4 seconds) and then try and
keep at that speed (velocity).
Sprinter Position
80
70
60
World Record:
100 meters in about 9.7 s
Top speed about
12 meters/second or
27 MPH
50
World Record
40
Grade 5: Fastest
30
20
Grade 5: Average
10
0
0
2
4
6
8
10
Time
12
14
16
18
World Record
Sprinter Velocity
Grade 5: Fastest
Velocity
15
Grade 5: Average
10
5
0
0
2
4
6
8
10
Time
12
14
16
18
Grade 5 Fastest
100 m in about 13.8 s
Top speed about
8 meters/second or
18 MPH
Grade 5 Fastest
100 m in about 17 s
Top speed about
7 meters/second or
15 MPH but fades at end.
Sprinter 40 m Split Times
World Record & Grade 5s
Position (meter)
40
Sprinter Position
30
20
World Record
Grade 5: Fastest
10
Grade 5: Average
0
0
2
4
Time
6
8
World Record
Velocity
Grade 5: Fastest
Grade 5: Average
10
5
0
0
2
4
Time
6
8
World Record:
40 meters in about 4.5 s
Top speed about
12 meters/second or
27 MPH
10
15
Sprinter Velocity
• Sprinters accelerate fairly
quickly (2 to 4 seconds) and
then try and keep at that speed
(velocity).
10
Grade 5 Fastest
40 m in about 6.5 s
Top speed about
8 meters/second or
18 MPH
Grade 5 Fastest
40 m in about 7.2 s
Top speed about
7 meters/second or
15 MPH and no fade! 1
Fast Cars over a ONE MILE Drag Strip
Friction
A force that happens when things
rub against each other.
Gravity
The force of attraction between all
masses in the universe
Frequency
The number of times something
happens within a given time period.