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Acceleration in changes - Sardis Secondary School · Describing Acceleration How can you calculate...

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Name: Unit 3 - Motion Chapter 9 Acceleration DAY OUTLINE KEY TERMS 1 Read 9.1 summaries (p. 193 in pckg) Assignment: Key Terms (9) (p. 192) Velocity & Acceleration w.s. (p. 194) Positive, negative and zero Acceleration (p. 194) 2 9.1 notes (p. 195-196) 1. Change in velocity Assignment: Read p.380-391 (text) 2. Acceleration p. 391 # 1,3,8,9 (p. 198) 3. Deceleration Calculating change in velocity w.s. (197) 3 9.1 QUIZ 4. Velocity-time graph 9.2 Notes (slides 1 -5) (p. 199) 5. Constant Acceleration Assignment: Read 9.2 Summary (p. 201 in pckg) 6. Average Acceleration Read p. 392-395 textbook p. 405 # 11-13 (p. 202) 9.2 Describing motion w.s. (p. 203) 4 9.2 Notes (slides 6-9) (p. 199-200) 7. Gravity Assignment: Read p.396-405 (text) 8. Acceleration due to Calculating Acceleration (p.204) gravity Analyzing vel-time graphs (p.205) 9. Air resistance Motion match up w.s. (p. 205) 5 Acceleration lab (9-2d) p.402-403 Due this class 6 Assignment: Ch.9 Review: Assessment 9.1, 9.2 (p. 208) p. 406-407 # 4, 6, 7, 1 1-14, 16-21 (p. 206-207 in pckg) Physics Unit w.s. (209) 7 Unit 3 Review: p. 413- 417 #4, 8-12, 14, 18-20, 24- 26, 29, 3 1-33, 36-5 1 (answers only for MIC Q.’s) (p. 210-211 inpckg) 8 Chapter 9 package due Unit 3 Test 1011
Transcript
Page 1: Acceleration in changes - Sardis Secondary School · Describing Acceleration How can you calculate a change in velocity? A change in velocity occurs when the speed of an object changes,

Name:

Unit 3 - Motion

Chapter 9 AccelerationDAY OUTLINE KEY TERMS

1 Read 9.1 summaries (p. 193 in pckg)Assignment:Key Terms (9) (p. 192)Velocity & Acceleration w.s. (p. 194)Positive, negative and zero Acceleration (p. 194)

2 9.1 notes (p. 195-196) 1. Change in velocityAssignment: Read p.380-391 (text) 2. Acceleration

p. 391 # 1,3,8,9 (p. 198) 3. DecelerationCalculating change in velocity w.s. (197)

3 9.1 QUIZ 4. Velocity-time graph9.2 Notes (slides 1 -5) (p. 199) 5. Constant AccelerationAssignment: Read 9.2 Summary (p. 201 in pckg) 6. Average Acceleration

Read p. 392-395 textbookp. 405 # 11-13 (p. 202)9.2 Describing motion w.s. (p. 203)

4 9.2 Notes (slides 6-9) (p. 199-200) 7. GravityAssignment: Read p.396-405 (text) 8. Acceleration due to

Calculating Acceleration (p.204) gravityAnalyzing vel-time graphs (p.205) 9. Air resistanceMotion match up w.s. (p. 205)

5 Acceleration lab (9-2d) p.402-403 — Due this class

6 Assignment:Ch.9 Review: Assessment 9.1, 9.2 (p. 208)

p. 406-407 # 4, 6, 7, 1 1-14, 16-21 (p.

206-207 in pckg)Physics Unit w.s. (209)

7 Unit 3 Review: p. 413- 417 #4, 8-12, 14, 18-20, 24-26, 29, 3 1-33, 36-5 1 (answers only for MIC Q.’s) (p.210-211 inpckg)

8 Chapter 9 package dueUnit 3 Test

1011

Page 2: Acceleration in changes - Sardis Secondary School · Describing Acceleration How can you calculate a change in velocity? A change in velocity occurs when the speed of an object changes,

Chapter 9: Acceleration KEY TERMS

Key Term Definition ExampleChange in velocity

Acceleration

Deceleration

Velocity-time graph

Constant acceleration

Average acceleration

Gravity

Acceleration due togravity

Air resistance

1°(L

Page 3: Acceleration in changes - Sardis Secondary School · Describing Acceleration How can you calculate a change in velocity? A change in velocity occurs when the speed of an object changes,

Des

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Page 4: Acceleration in changes - Sardis Secondary School · Describing Acceleration How can you calculate a change in velocity? A change in velocity occurs when the speed of an object changes,

Dat

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6.

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Page 5: Acceleration in changes - Sardis Secondary School · Describing Acceleration How can you calculate a change in velocity? A change in velocity occurs when the speed of an object changes,

9.1 Describing Acceleration — Student Notes

+ An object travelling with

______________________

+ An object travelling with non-uniform motion will:

‘have different

______________________________

‘take different

__________________________________

•have a continuously

__________________________

has equal displacements in equal time intervals.

during equal time intervals.

to travel equal displacements.

Changes in Velocity

• A change in velocity (z) occurs when the

+ A change in______________________

+ If the change in velocity is

of an object changes, or its

______

changes, or both.

can be calculated by: A = —

, the object is travelling with

Positive Changes in Velocity

• If the change in velocity is the (+, -) as the initial velocity, the speed of the object is

Example: i = Vf — +9mIs - (+6mIs) = + 3mIs

Negative Changes in Velocity

• If the change in velocity is the

______________________

object is

Example: i = — = + 2mIs - (+9mIs) = - 7mIs

Acceleration

• isthe

.

(+, -) of the initial velocity, the speed of the

the change in

_____________________

can be due to a change in

_______________________

a change in

_____________________________,

or both.

• two objects with the

__________________________

can have

_________________________

> this is because acceleration describes

_______________________________________________

• Example: Suppose both of these vehicles, starting from rest, speed up to 60 knilh. They will have

the

___________________________

but since the dragster can get to 60 1cm/h faster than the old

car, the

Page 6: Acceleration in changes - Sardis Secondary School · Describing Acceleration How can you calculate a change in velocity? A change in velocity occurs when the speed of an object changes,

Positive Acceleration• The is the same as the

acceleration

velocity

Example#1: A car in the

________________________

direction.

If we designate the forward direction as

_________

(+) then the change in velocity is

____________________

therefore the acceleration is

________________

(+).

____________________________direction.

If we designate the forward direction as

__________________________________________

therefore the acceleration is —

Positive and Negative Acceleration *Remember positive (+) and negative (-) refer to directions.*

• Example#3: A

___________________________

in the

_____________________

direction.

> If we designate the backward direction as

_________________________

then the change in

velocity is

____________________________

therefore the acceleration is negative (-) even

though the car is increasing its speed.

Av =i — =z(—4m/s)—(—lm/s)=—3m/s=

ma’s

• Example#4: A

_________________________

in the

> If we designate the backward

____________________________as

negative (-) then the

__________________________________is

positive (+), therefore the

___________________

is

positive (+) even though the car is

_________________________

its speed.

=f—I=(—1mIs)—(—4m/s)=+3m/s=

vf——lm!s v1=—4mts-

Negative Acceleration

• Acceleration that is

_________

of motion is sometimes called

• Example#1: A car_____

the directionacceleration

oci +in the

(+) then the change in velocity is

direction.

Page 7: Acceleration in changes - Sardis Secondary School · Describing Acceleration How can you calculate a change in velocity? A change in velocity occurs when the speed of an object changes,

ApplyingName Date Knowledge

Use with textbook page 382.

Calculating change in velocity1. Complete the following table by calculating the missing quantities. Positive (+)

represents the forward motion. Use the formula A7 = — . In the last column,describe the change in velocity (e.g. object is slowing down, object is speeding up,or object is in uniform motion),

V V1 Description of Ai+ 14 mIs + 5 rn/s object is slowing down+BmIs Om/s

+25 mIs +12m/s+20m/s —3Dm/s—38m/s —1Dm/s

—16m/s Om/s—3m/s +22m/s

2. Use the following data table to calculate the change in velocity for each time interval.Suppose motion toward north is positive (+).

Time (s) Velocity (mis)0 0

10 1520 2830 2840 2250 12

a) Os—lOs.

b) lOs—20s

c) 20s—30s

d) 30s—40s

e) 40s—50s

© 2008 McGraw-Hill Ryerson Limited Section 9.1 Describing Acceleration • MHR 167

Page 8: Acceleration in changes - Sardis Secondary School · Describing Acceleration How can you calculate a change in velocity? A change in velocity occurs when the speed of an object changes,
Page 9: Acceleration in changes - Sardis Secondary School · Describing Acceleration How can you calculate a change in velocity? A change in velocity occurs when the speed of an object changes,

9.2 Calculating Acceleration — Student Notes

Calculating Acceleration:The

_____________________

of an object depends onthe

________________________________and

the

_____________required

to change the velocity.When stopping a moving object, the relationship between time and acceleration is:

_________________________

the stopping time

_________________________

the acceleration

• the stopping time

_________________________

the acceleration

Velocity-Time Graphs:

• The motion of an object with

________________________________

is best represented by a

The motion of an object with

graph.

is best represented by a

________

graph.

Velocity vs. Time

Time (s)

The slope of a velocity-time graph is

. is measured in

_______

Determining Motion from a Velocity-Time Graph:

. slope (in the

acceleration) object’s velocity is

_____

direction.

0

‘a

to0

.

.

______________

slope(______________

_____________________slope

(________

in the

acceleration) — object’s velocity is

______________

— acceleration) — object’s velocity is

— direction or the object’s velocity is

40

30

20C,0

10

slope riserun

= 50m/s—25m(s4.0s — 2.0 5

- 25 mIs2.Os

= 13m1s2

:..............z.:..z.:::

1 2 3 4

increasing in the negative direction.

Velocity vs. Time

0

During which time interval was

• The acceleration zero?

• The acceleration negative?

• The acceleration positive?

• The object increasing it’s velocity north?• The object decreasing it’s velocity north?• The object moving at a constant velocity north?

Time (s)

qC

Page 10: Acceleration in changes - Sardis Secondary School · Describing Acceleration How can you calculate a change in velocity? A change in velocity occurs when the speed of an object changes,

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kth

atfa

llsfo

r3.

5s?

Mor

ePr

actic

e:1.

Atr

uck

star

ting

from

rest

acce

lera

tes

unif

orm

lyto

18m

/s[W

jin

4.5

s.W

hati

sth

etr

uck’

s

acce

lera

tion?

2.A

ball

isth

row

nst

raig

htup

into

the

air

at14

rn/s

. How

long

does

itta

kefo

rth

eba

llto

slow

dow

nto

anup

war

dve

loci

tyof

6.0

mIs

?

2.A

tobo

ggan

mov

ing

5.0

rn/s

forw

ard

dece

lera

tes

back

war

dsat

-0.4

0m

Is2

for

10s.

Wha

t is

the

tobo

ggan

’sve

loci

tyat

the

end

ofth

e10

a?

3.A

rock

isth

row

ndo

wnw

ards

with

anin

itial

velo

city

of8.

0m

Is.

Wha

tis

the

velo

city

ofth

ero

ckaf

ter

1.5

s?

3.H

owm

uch

time

does

itta

kea

car,

trav

ellin

gso

uth

at12

ni’s

, to

incr

ease

itsve

loci

tyto

26m

/s

sout

hif

itac

cele

rate

sat

3.5

nifs

2so

uth?

Page 11: Acceleration in changes - Sardis Secondary School · Describing Acceleration How can you calculate a change in velocity? A change in velocity occurs when the speed of an object changes,

Text

book

page

s39

2—40

5

Bef

ore

You

Rea

d

Sum

mar

y

How

isac

cele

rati

on

det

erm

ined

ona

velo

city

-tim

egra

ph?

Ave

loci

ty-t

ime

grap

hre

pres

ents

the

mot

ion

ofan

obje

ctw

ithch

angi

ngve

loci

ty.

The

slop

eof

ave

loci

ty-t

ime

grap

hgi

ves

the

obje

ct’s

acce

lera

tion,

whi

chis

mea

sure

din

rn/s

2.W

hen

abe

st-f

itlin

epa

sses

thro

ugh

all

data

poin

ts,

the

obje

ct’s

velo

city

isch

angi

ngat

aco

nsta

ntra

tean

dit

expe

rien

ces

cons

tant

acce

lera

tion

.H

owev

er, s

ince

not

all

the

velo

citie

sm

aybe

dire

ctly

onth

ebe

st-f

itlin

e,th

esl

ope

isre

ferr

edto

asav

erag

eac

cele

rati

on(a)

.If

nort

his

cons

ider

edpo

sitiv

e,fo

rlin

esab

ove

the

x-ax

is:

•a

posi

tive

slop

e(a

)re

pres

ents

the

aver

age

acce

lera

tion

ofan

obje

ctth

atin

crea

ses

spee

dat

aco

nsta

ntra

tew

hile

trav

ellin

gno

rth.

Acc

eler

atio

nis

cons

tant

and

posi

tive.

•ze

rosl

ope

(b)

repr

esen

tsan

obje

cttr

avel

ling

nort

hat

aco

nsta

ntsp

eed.

Itis

not

acce

lera

ting.

•a

nega

tive

slop

e(c

)re

pres

ents

anob

ject

that

decr

ease

ssp

eed

ata

cons

tant

rate

whi

letr

avel

ling

north

.A

ccel

erat

ion

isco

nsta

ntan

dne

gativ

e.V

eloc

ityis

posi

tive.

Vel

ocity

vs.T

ime

tito

tTh

ee(of

Alin

ebe

low

the

x-ax

is(d

)re

pres

ents

incr

easi

ngsp

eed

ata

cons

tant

rate

tow

ard

the

sout

h.A

ccel

erat

ion

isco

nsta

ntan

dne

gativ

e.V

eloc

ityis

nega

tive.

Rec

all

that

aver

age

acce

lera

tion

isth

esl

ope

ofa

velo

city

-tim

egr

aph:

Slop

e=

rise

1:v

=

Thi

ste

xtbo

okon

lyco

nsid

ers

situ

atio

nsw

here

acce

lera

tion

isco

nsta

nt. T

his

mea

nsav

erag

eac

cele

ratio

nis

actu

ally

the

sam

eas

acce

lera

tion

atan

yin

stan

t.-

1wa=

OT

his

equa

tion

can

bere

arra

nged

toca

lcul

ate

velo

city

ortim

e.Fo

rve

loci

ty:

For

time:

Wha

tis

the

rela

tion

ship

bet

wee

ngr

avit

yan

dac

cele

rati

on

?

Whe

nan

obje

ctfa

llsne

arE

arth

’ssu

rfac

e,th

efo

rce

ofgr

avit

ypu

llsit

dow

nwar

d.C

onsi

der

aba

llbe

ing

thro

wn

stra

ight

upin

toth

eai

r,w

here

“up”

ispo

sitiv

e.•

On

the

way

up,

the

ball’

sve

loci

tyis

decr

easi

ng.

The

ball

issl

owin

gdo

wn,

soits

acce

lera

tion

isne

gativ

e.•

At

itsm

axim

umhe

ight

,th

eba

ll’s

velo

city

isze

rofo

ran

inst

ant

sinc

eth

edi

rect

ion

ofth

eba

llis

chan

ging

.(B

ecau

seth

eba

ll’s

velo

city

isst

illch

angi

ng,

the

ball

isac

cele

ratin

gal

thou

ghits

velo

city

isze

rofo

ran

inst

ant.)

•W

hen

the

ball

star

tsto

com

edo

wn,

itssp

eed

incr

ease

s.H

owev

er,

itsve

loci

tyis

nega

tive

beca

use

the

ball

ishe

adin

g“d

own.

”T

heba

ll’s

acce

lera

tion

isne

gativ

e.

How

does

air

resi

stan

cein

flue

nce

acce

lera

tion

due

togr

avit

y?

Obj

ects

fall

atdi

ffer

ent

rate

sbe

caus

eof

air

resi

stan

ce,

afr

ictio

n-lik

efo

rce.

Inth

eab

senc

eof

air

resi

stan

ce,

all

obje

cts,

rega

rdle

ssof

thei

rw

eigh

t,fa

llw

ithth

esa

me

cons

tant

acce

lera

tion

of9.

8m

/s2

dow

nwar

d.T

his

isac

cele

rati

ondu

eto

grav

ityCs

).In

man

ysi

tuat

ions

,th

eai

rre

sist

ance

actin

gon

afa

lling

obje

ctis

sosm

all

that

we

can

assu

me

the

obje

ctha

sa

cons

tant

acce

lera

tion

of—

9.8m

/s2,

whe

reup

isp

osi

tiv

e.

Nam

eD

ate

Cal

cula

ting

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eler

atio

n

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ime

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hm

ight

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omth

epo

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egr

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tin

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rati

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ula

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ph

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Page 12: Acceleration in changes - Sardis Secondary School · Describing Acceleration How can you calculate a change in velocity? A change in velocity occurs when the speed of an object changes,

-

LcJ

Page 13: Acceleration in changes - Sardis Secondary School · Describing Acceleration How can you calculate a change in velocity? A change in velocity occurs when the speed of an object changes,

Nam

e:__

____

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lock

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isco

nsta

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ing

velo

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time

grap

h

wou

ldbe

aho

rizo

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line

draw

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oci

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Page 14: Acceleration in changes - Sardis Secondary School · Describing Acceleration How can you calculate a change in velocity? A change in velocity occurs when the speed of an object changes,

ApplyingName Date Knowledge

Use with textbook pages 396—400.

Colculafing acceleration1. What is the formula for each of the following quantities?

(a) acceleration (b) change in velocity (c) time interval

2. Complete the following table. Use the motion formula to calculate the missing

quantities. Show all your work and use the correct units.

Change in Time Acceleration Formula Used andVelocity Calculation Shown140 rn/s 8s 17.5 rn/s2

t 8

—60km/h 4hV

120 km/h 48 km/h2

15s —3.5 rn/s2V 12m/s 2.5s

—25 m/s —1 2.5 rn/s2

• 9.6 h 5 km/h2

3. Solve each problem using the appropriate motion formula. Show all your work anduse the correct units.

a) A car moving north goes from 5.56 rn/s to 63.9 rn/s in 7.5 s. What is theacceleration?

b) If a sprinter starts a race and has an acceleration of 2.4 m/s2 in 2.5 s, what is hisfinal velocity, assuming the initial velocity is 0 m/s2?

c) A rock accelerates at —9.8 rn/s2 when falling. How long does it take to change itsvelocity from —4.5 rn/s to —19.4 m/s?

d) A satellite released from a stationary space shuttle accelerates to +68 rn/s2 in25 s. What is its change in velocity?

172 MHR • Section 9.2 Calculating Acceleration © 2008 McGraw-Hill Ryerson Limited

2cL..

Page 15: Acceleration in changes - Sardis Secondary School · Describing Acceleration How can you calculate a change in velocity? A change in velocity occurs when the speed of an object changes,

NA

Ma

04

1012

Tim

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ompl

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foll

owin

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.D

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rati

on,

and

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city

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rite

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nth

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esp

ace.

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will

notn

eed

tous

eev

ery

term

.

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mot

ion

with

noch

ange

insp

eed

ordi

rect

ion

2.—

aph

ysic

alqu

antit

yth

atha

sm

agni

tude

but n

odi

rect

ion

3.de

scri

bes

how

muc

han

obje

ct’s

posi

tion

has

chan

ged

4.th

eto

tall

engt

hof

ajo

urne

yth

atan

obje

ctta

kes

5.—

desc

ribe

sho

wfa

stan

obje

ctis

mov

ing,

but n

otits

dire

ctio

n6.

diff

eren

cebe

twee

nin

itial

time

and

final

time

7.—

the

loca

tion

ofan

obje

ctas

seen

byan

obse

rver

8.qu

antit

yw

ithbo

thm

agni

tude

and

dire

ctio

n

9.fr

ictio

n-lik

efo

rce

10.

9.8

m/s

3

11.—

can

bea

smoo

thcu

rve

orsc

raig

htlin

e

12.

allo

ws

usto

pict

ure

orvi

sual

ize

mot

ion

13.—

desc

ribe

sth

esp

eed

and

dire

ctio

nof

mot

ion

14.—

occu

rsw

hen

the

spee

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anob

ject

chan

ges,

orits

dire

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mot

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chan

ges,

orbo

th

15.—

acce

lera

tion

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isop

posi

teto

the

dire

ctio

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mot

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16.—

the

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anob

ject

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loci

ty(i

ncre

ase

orde

crea

se)

ina

give

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riod

oftim

e

17.—

rate

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ange

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sitio

nfo

ra

time

inte

rval

18.

whe

nan

even

tocc

urs

19.

the

rise

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grap

hov

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run

20.—

repr

esen

ted

byth

esl

ope

ona

velo

city

-tim

egr

aph

(b)

2s

—6

5—

(c)6

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atch

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elin

e

____

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____

____

____

____

____

____

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____

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Use

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ph

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ata

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Page 16: Acceleration in changes - Sardis Secondary School · Describing Acceleration How can you calculate a change in velocity? A change in velocity occurs when the speed of an object changes,

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Page 17: Acceleration in changes - Sardis Secondary School · Describing Acceleration How can you calculate a change in velocity? A change in velocity occurs when the speed of an object changes,

Zc7

Page 18: Acceleration in changes - Sardis Secondary School · Describing Acceleration How can you calculate a change in velocity? A change in velocity occurs when the speed of an object changes,

II.ç=

45km

lhjn

orth

l;c=6

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Tim

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ime

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on8.

Tim

e(s

)

8.W

hat

isth

eob

ject

’sac

cele

rati

onbe

twee

nth

eti

me

inte

rval

2s

and

4s?

A.-

j-lr

n/s

2 B.+1

0in

/s2

C.+2

0rn

/s2

D.+4

0ni/

s2

Use

with

text

book

page

s38

2—38

6.

Des

crib

ing

acce

lera

tio

nC.

the

obje

ctre

mai

nsat

rest

Nam

e

Mat

chth

eTe

rmon

the

left

with

the

best

Des

crip

tor

onth

eri

ght.E

ach

Des

crip

tor

may

beus

edon

lyon

ce.

Dat

esm

eJ

Use

with

text

book

page

s39

2-40

0.

Cal

cula

ting

acce

lera

tio

nM

atch

the

Des

crip

tor

onth

ele

ftw

ithth

ebe

stV

eloc

ity-T

ime

Gra

phon

the

righ

tTh

eV

eloc

ity-

lim

eG

raph

sre

pres

ent t

hem

otio

nof

aca

rhea

din

gno

rth.E

ach

Vel

ocity

-Tim

eG

raph

may

beus

edon

lyon

ce.

1._

acce

lera

tion

A.r

ate

atwh

ichan

obje

ct2.

dece

lera

tion

chan

ges

itsve

locit

y3.

cons

tant

velo

city

B.an

obje

cttra

velli

ng4.

chan

geIn

with

unifo

rmm

otio

nin

velo

city

astr

aigh

tline

C.ac

cele

ratio

nin

adi

rect

ion

that

isop

posit

eto

the

dire

ction

ofec

tico

D.ch

ange

that

occu

rsw

hen

the

spee

dof

anob

ject

chan

ges,

orits

dire

ction

ofm

otio

nch

ange

s,or

both

I,=

3.5m

/s[e

ast]

;=7.

5rnl

s[ea

st}

1.Th

eca

rIs

stopp

ed.

2..._

......

.The

car i

sac

cele

ratin

g.3.

The

car i

sslo

wing

down

.4.

The

cari

stra

velli

ngat

cons

tant

velo

city.

D.no

thin

gha

ppen

sto

the

obje

ct

7.Su

ppos

ean

obje

ctm

ovin

gfo

rwar

dch

ange

sits

velo

city

from

15rn

/sto

6m

/s.W

hat i

sth

ech

ange

inve

loci

ty?

A.—

21m

/s

B.—

9rn/

s

C.9

rn/s

D.2

1rn/

s

8.W

hich

ofth

efo

llow

ing

have

anac

cele

ratio

nin

the

sam

edi

rect

ion

asth

eob

ject

’sm

otio

n?

A.I

andll

on.l

y

B.I

andll

lonly

C.f

landli

lonly

D.I

,II,

and

ffl

9.W

hich

ofth

efo

llow

ing

are

true

abou

tac

celis

ratio

n?

A.I

andfl

on

ly

D.I

,IJ,

andff

l

The

Is) N

C.

lime

(ci

0.

a.

rena

Is

Cir

cle

the

lett

erof

the

bes

tan

swer

.

5.T

heto

rtoi

sem

oved

slow

lyan

dst

eadi

ly.

The

hare

ran

quic

lcly

,th

enfe

llas

leep

near

the

fini

shlin

e.Id

enti

fyth

efo

llow

ing

quan

titie

sas

scal

aror

vect

or,

resp

ectiv

ely:

the

aver

age

velo

city

ofth

eto

rtoi

sedu

ring

the

entir

era

ce,

the

acce

lera

tion

ofth

eha

redu

ring

the

firs

t2

min

utes

ofth

era

cean

dth

etim

eit

take

sfo

rth

eto

rtoi

sean

dth

eha

reto

fini

shth

era

ce.

A.

vect

or,

vect

or,

scal

ar

B.sc

alar

,sc

alar

,ve

ctor

C.ve

ctor

,sc

alar

,ve

ctor

0.sc

alar

,ve

ctor

,sc

alar

6.If

the

acce

lera

tion

ofan

obje

ctis

inth

eop

posi

tedi

rect

ion

asth

eve

loci

ty,

whi

chof

the

follo

win

gha

ppen

s?

)A.

the

obje

ctsp

eeds

up

B.th

eob

ject

slow

sdo

wn

B.la

ndif

ion

ly

C.R

and

III

only

5.A

ccel

erat

ion

isre

pres

ente

dby

the

slop

eof

a

A.

velo

city

-tim

egr

aph

B.po

sitio

n-tim

egr

aph

C.di

stan

ce-t

ime

grap

h

D.ac

cele

ratio

n-tim

egr

aph

6.A

met

eor

goes

from

+1.0

kin/

sto

÷2.2

km/s

in0.

04s.

Wha

t is

itsac

cele

ratio

n?

A.0.

031c

m/s

2

B.3

0k

m/s

2

C.55

km

/s2

D.8

0k

m/s

2

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Page 19: Acceleration in changes - Sardis Secondary School · Describing Acceleration How can you calculate a change in velocity? A change in velocity occurs when the speed of an object changes,

Physi

csU

nit(r

no

çoc.

Ao

ua()

1.(a

)A

car

mov

esea

stal

ong

ahi

ghw

ayat

90.0

krnl

hfo

rI

han

d15

mm

.Wha

tis

the

car’

sdi

spla

cem

ent?

(b)

How

long

will

itta

kefo

ra

pers

onw

alki

ngat

3.8

rn/s

nort

hto

mov

e12

5m

?

2.A

car

star

tsfr

omre

stan

dac

cele

rate

sat

ast

eady

rate

,re

achi

nga

fina

lve

loci

tyof

24.0

rn/s

in1

2s.

(a)

Cal

cula

teth

eac

cele

rati

onof

the

car.

(b)

Cal

cula

teth

eav

erag

eve

loci

tyof

the

car.

6.H

owm

any

seco

nds

will

itta

kea

spee

dboa

ttr

avel

ling

at70

.0km

/h[S

]to

cove

ra

dist

ance

of5.

0km

?

7.D

onov

anB

aile

yse

tthe

wor

ldin

door

trac

kre

cord

in19

96by

runn

ing

forw

ard

50m

inju

st5.

56s.

Wha

t was

Bai

ley’

sav

erag

eve

loci

ty?

8.A

boat

trav

els

acro

ssa

450

mla

kew

ithan

aver

age

forw

ard

velo

city

of5.

0rn

/s.

How

muc

htim

edo

esit

take

for

this

boat

tocr

oss

the

lake

?

9.T

hem

otio

nof

anel

evat

oris

repr

esen

ted

byth

epo

sitio

n-tim

egr

aph

belo

w.

Des

crib

e,us

ing

wor

ds,

the

mot

ion

ofth

eel

evat

ordu

ring

the

30s

time

inte

rval

.

0-l

os:

10-2

0s:

20-3

0s:

Posi

tion

vs.T

ime

(c)

Wha

tis

the

tota

ldi

spla

cem

ent

ofth

eca

r?

3.A

sing

le-e

ngin

eai

rpla

nele

aves

anai

rpor

tan

dfl

ies

toan

othe

rai

rpor

t85

0km

nort

h.It

take

s4.

0h

toco

mpl

ete

the

flig

htW

hat

isth

eve

loci

tyof

the

airp

lane

?

4.A

truc

ktr

avel

sfr

omC

ityA

due

wes

tto

City

B,a

dist

ance

of21

0km

.T

heto

tal

tim

efo

rth

etr

ipis

two

hour

san

dfi

ftee

nm

inut

es.

Wha

tis

the

aver

age

velo

city

ofth

etr

uck?

5.A

bus

trav

els

from

City

Xdu

eea

stto

war

dC

ityY

.If

the

bus

trav

els

atan

aver

age

velo

city

of90

km/h

[Ej,

wha

t will

beth

edi

spla

cem

ent

ofth

ebu

s4.

5h

late

r?

..:

L.

::7..

-

-4E

i-4

-•.

--

-.-

-

------

7.

.-

-_

4../..

..

‘-

-

--

-.

--

:1:-

:sL: :

:i

,.

20

...

-

10. A

syo

uap

proa

cha

tow

nw

hile

you

are

driv

ing,

you

take

your

foot

off t

heac

cele

rato

r.T

heca

rsl

ows

dow

nfr

om90

km/h

[S]

to50

km/h

[S)

in8.

0s.

Wha

tis

the

acce

lera

tion

ofth

eca

r?

11.

Aro

ckfa

llsfr

omth

eto

pof

ahi

ghcl

iff.

How

long

wou

ldit

take

this

rock

tore

ach

ave

loci

tyof

25rn

/sdo

wnw

ard?

(Hin

t:ac

cele

rati

ondu

eto

grav

ityis

9.8

m/s

2do

wn)

Page 20: Acceleration in changes - Sardis Secondary School · Describing Acceleration How can you calculate a change in velocity? A change in velocity occurs when the speed of an object changes,

Ph ictr t 0 q i ‘419__‘-_-?-- LI I*-) zq -‘i-—j

3,31

z’o

Page 21: Acceleration in changes - Sardis Secondary School · Describing Acceleration How can you calculate a change in velocity? A change in velocity occurs when the speed of an object changes,

2d1


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