05 Motion.pptx

(1)

I can . . .

• explain the difference between

average

speed

and

instantaneous

speed

.

• explain the difference between

speed

and

velocity

.

• _{explain the difference between}

_velocity

_and

acceleration

.

• _{explain the}

_{meaning of the slope}

_{of a graph}

involving

position

,

velocity

, or

acceleration

with respect to

time

.

• _{recognize the appropriate units of each}

(2)

Rate

is defined as:

Any Quantity

divided by

Time

Examples:

Inches of Rain

per

Hour

Pizzas

per

Day

Vibrations

per

(3)

Speed

is the

RATE

at which your

position changes

(4)

http://galenfry.com/nz/devon11.jpg

LINEAR MOTION

Is this car “moving”?

(5)

(6)

(7)

(8)

http://commons.wikimedia.org/wiki/File:Clouds_over_the_Atlantic_Ocean.jpg

http://1.bp.blogspot.com/-p304Z4BxlOI/T6l6H5l231I/AAAAAAAANK0/ZsIm2jbM_s8/s1600/20120413%2BTexoma%2B3454%2B74%2Bspinnaker%2Bout%2BJ122%2BSecond%2BStar.jpg

Relative Motion

15 knot wind

15 knot sailboat

(9)

Average

Speed

Change in Position

Time

∆

x

t

≡

÷

http://www.clarkstopwatch.qpg.com/

≡

x

₀

x

_f

x

_f

- x

₀

t

(10)

x

₀

_{2 seconds}

x

_f

x

_f

_{2 seconds}

x

₀

x

₀

_{2 seconds}

x

_f

Average

Speed

Change in Position

Time

≡

x

_f

- x

₀

t

≡

=

8 - 2

₂

= 3

= 2 - 8

2 = -

3 =

3 - (-3)

2

(11)

Average

Speed

=

÷

Distance

Time

(12)

miles

hour

meters

second

centimeters

year

inches

minute

(13)

Fundamental Units

M.K.S. System

M

eters

K

ilograms

(14)

All Possible Units

American

Metric (SI)

M.K.S

Thingamajigs

(15)

328 ft

19.678 s

=

16.7 ft

s

1 mi

5280 ft

3600 s

1 hr

(16)

Road Trip

0

5

10

15

20

25

30

0

5

10

15

20

25

30 T ime (minutes)

(17)

Average Speed ≡

∆

_∆

Position

_Time

Slope ≡

Rise

Run

=

∆

Y

∆

X

Road Trip

0

5

10

15

20

25

30

0

5

10

15

20

25

30 T ime (minutes)

(18)

Average Speed ≡

Slope ≡

Rise

Run

=

∆

Y

∆

X

∆

Position

∆

Time

Road Trip

0

5

10

15

20

25

30

0

5

10

15

20

25

30 T ime (minutes)

(19)

6,378 km

40º

= 1670 km/hr

Speed =

40,070 km

_{24 hr}

Circumference = 2·π·6,378 km

= 40,070 km

(20)

939,336,203 km

365 days

1 day

24 hr

=

107,000 km/hr

Circumference = 2·π·149,500,000

= 939,336,203 km

149,500,000 km

(21)

246,000,000

,000,000 km

223,000 years

220 km/sec

(22)

If a car has an average speed of 48.3 meters per second,

how long will it take to travel a distance of 6,740 m?

(23)

V

=

d

_t

If a car has an average speed of

48.3 meters per second

,

how long

will it take to travel a distance of

6,740 m

?

48.3 =

6740

_t

t

48.3 t

=

6740

48.3 t

= 1.40 x 10

2

48.3 Write down the EQUATION!

Plug numbers into

the EQUATION!

(24)

Instantaneous

Speed

(25)

Av

era

ge

sp

ee

d f

rom

3 to

6 s

ec

on

ds

Av

era

ge

spe

ed

fro

m 3

to

4 s

eco

nds

Inst

anta

neo

us s

pee

d at

3 s

eco

nds

5 seconds

27

0 m

et

er

s

Av

er

ag

e s

pe

ed

fr

om

3 to

8 se

co

nd

(26)

Is driving

1100 miles

in 13 hours

reasonable

?

Average

Speed

=

Distance

_Time

1100 miles

13 hours

=

85 mi

hr

(27)

50 mph

100 mph

0 mph

67 mph

125 mph

67 mph

85 mph

AVERAGE

NO!

68 mph

50 +

100 +

0 +

67 +

125 +

67

(28)

Which ball gets to the finish line first?

A

B

“B”

(29)

Velocity

≡

Speed

in a Given

DIRECTION

SPEED

:

55 miles

_hour

VELOCITY

:

55 miles

_hour

East

(30)

180 mp

h

(31)

180 mp

h

180 m

_ph

Same

SPEED

(32)

Acceleration

∆

V

t

≡

Change in Velocity

Time

≡

÷

50 miles

_hour

70 miles

_hour

10 sec

(33)

Acceleration

_≡

∆

Velocity

_Time

70 – 50

10 sec

=

mi

hr

=

2 mi

hr

sec

= 2

_hr

_·

mi

_sec

V

_f

– V

₀

(34)

0

10

20

30

40 50 60 70 80

90

100

110

120

130 miles per hour

0

10

20

30

40 50 60 70 80

90

100

110

120

130 miles per hour

Acceleration

= 10 mi/hr/s

?

Acceleration

= 5 mi/hr/s

?

(35)

Name THREE controls on car that

cause the car to

ACCELERATE

.

• Gas (accelerator)

• Brake

• Steering Wheel

(36)

70 mph

Acceleration is a CHANGE in VELOCITY over time.

You can change your velocity by EITHER

(37)

(38)

http://media.putfile.com/Motorcycles---Hayabusa--220--mph

Acceleration

= ?

Time = 25 seconds

V

_f

– V

₀

t

Acceleration

=

220 – 0

25 =

= 8.8

_hr·s

mi

(39)

Acceleration ≡

∆

_∆

Velocity

_Time

Slope ≡

Rise

Run

=

∆

Y

∆

X

Av

era

ge

Ac

ce

ler

(40)

(41)

Acceleration

= ?

Time = 2.9 seconds

V

_f

– V

₀

t

Acceleration

=

95 – 45

2.9 =

= 17

_hr·s

mi

(42)

Acceleration

= ?

Time = 5.8 seconds

V

_f

– V

₀

t

Acceleration

=

200 – 150

5.8 =

= 8.6

mi

hr·s

(43)

Acceleration

= ?

V

_f

– V

₀

t

Acceleration

=

220 – 220

15 =

= zero

mi

hr·s

Time = 15 seconds

(44)

Time = 11 seconds

V

_f

– V

₀

t

Acceleration

=

120 – 220

11 =

= - 9.1

mi

hr·s

Acceleration

= ?

(45)

Mach 1 = 761 mi/hr

V

_f

– V

₀

t

Acceleration

=

761 – 0

29 =

= 26

mi

(46)

Road Trip

0

10

20

30

40

50

60

0

5

10

15

20

25

30

(47)

Road Trip

0

10

20

30

40

50

60

0

5

10

15

20

25

30

(48)

Road Trip

0

10

20

30

40

50

60

0

5

10

15

20

25

30

(49)

1 ft

2 ft

3 ft

4 ft

5 ft

(50)

Acceleration

∆

v

t

a

=

Change in

Velocity

Time

≡

m

s

a

= 5

m

s

· s

a

= 5

m

s

2 a

= 5

(51)

(52)

m

s

2 Acceleration

= 5

EVERY

second the

velocity

changes by

5 m/s

V

_f

= a·t

35

7

30

6

25

5

20

4

15

3

10

2

5

1

0

0 Instantaneous

Velocity

(m/s)

Time

(

seconds)

V

_f

= 5·0 = 0

V

_f

= 5·1 = 5

V

_f

= 5·2 = 10

V

_f

= 5·3 = 15

V

_f

= 5·4 = 20

V

_f

= 5·5 = 25

V

_f

= 5·6 = 30

V

_f

= 5·7 = 35

What is the instantaneous velocity after 30 seconds?

(53)

v

_x

= +100 m/s + (5 m/s

2 )(30 s)

= 250 m/s

v

_x

= +100 m/s + (- 5 m/s

2 )(30 s)

= -50 m/s

v

_x

= -100 m/s + (- 5 m/s

2 )(30 s)

(54)

I can . . .

• explain the difference between

average

speed

and

instantaneous

speed

.

• explain the difference between

speed

and

velocity

.

• _{explain the difference between}

_velocity

_and

acceleration

.

• _{explain the}

_{meaning of the slope}

_{of a graph}

involving

position

,

velocity

, or

acceleration

with respect to

time

.

• _{recognize the appropriate units of each}