UNIT #1 KINEMATICS - Mr.Neave's Websitemrneave.weebly.com/uploads/1/3/5/9/13590915/big_5... ·...
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UNIT #1 KINEMATICS The Big 5
Transcript of UNIT #1 KINEMATICS - Mr.Neave's Websitemrneave.weebly.com/uploads/1/3/5/9/13590915/big_5... ·...
UNIT #1 KINEMATICS The Big 5
Uniform Acceleration
� acceleration is constant
� 5 Kinematic equations...much easier than graphical analysis!
Equation #1
� v-t graph, straight line (uniform acceleration)
� Δd = area under graph Δd=Atriangle + Arectangle
A triangle
IbtffuiilA Red.;¥#jmVz
in⇒¥¥9*Ek÷*¥÷t
Attal ? ATriangle
+ Arectangle
=otEi¥ + ate)
= atly.it + ¥vI=
at(v?vD+2atv÷state+2¥⇐tz±
aEd t.EE#
Equation #2
� we know that
� we can say,
� rearranging, we get
Equation #3
� we can use equations (1) and (2) to derive equation (3)
(1) (2)
c.) ←€tktion
The Big Five
Equation Missing Variable
(1)
(2)
(3)
(4)
(5)
Examples
1. A car accelerates at 3m/s2 from rest for 10s. How far does it travel?
2. A car is moving at 100km/h. It stops in 5.0s.
What is the car’s acceleration?
YifGigi,
,o Required: oedistana
9=3%2 Analysis. 1st = los
d=htttzat2
ot#; at'
:nasat
'
d.ge#osjd=tzf3g.jlo0s/d=ts(3oon
)D= 150mi
$2.
GiveToo kn/hat = 5. Os
Vz = Omls ( stopped)Required @ = acceleration
.
Analyst vz TV , tart
steps :
iool#×wqo÷g×h±*×Y#ov. . 27.8mA
Vz = Vi tat ( subtract V , from
both sides )vz . Vi = at
( divide both sides
12ft = a by t )
Omls - 27.8ns = a
÷; .a= - 5.61
-27.8Mt =9 5
SOS
Homework
� Read 1.5
� p.39#1-6 0GRASS
÷Red . / Retest
- Missed quizzes ( 2 No monks
IF youwrite all
quizzes2 lowest get
removed )Extra Hdttuesiethurelmd.
t.FI#Edna
6¥-77€art A wins by 27 seconds
.
# : iv=u=5.com/sVz=7.5m/sd=50.0m
Required: a= acceleration
.Anti: vi .vi+2ad
steepa=hY÷a
-31.2532adf.se# a
2( son )at 56.25
;n÷ -25¥ a= 0.3125%2÷ .
'. a=O.31m/s2
Pg ,39*6
aaorigin
.
¥oEfj . song8,
. OmkEd = 4.50×102 mfp
.
Required E- accelerationn°
Analysis : Ed.Fattyaati. 4.5×102n[up=tE(4.04=4.5×102
m[ up]=(8s2Tag=45gxlghG=to= 56 m1s[up]
q°
b) Is =P,treat
I =a÷sbngfup] × 4.0$
Th = 224 mls [up]
in = 220 m/s[vp]. Az j, g digs
Pg . 42 #:G
jogsIsGig 8
,
-
. 8.3mg [ up]
£= 98% .[down]
Required:max height = Ed max
Analysing at max height vz=on/s
Yi .. vii. 2kdd q+Ep]
f⇒=8f⇒t2f9e⇒od0 ;I= 68.89;D - 19.6¥ Ad
0¥ - 68.89 ;D = -tbng Ad
-68.89mg.
=-
19.6mg ad
Ed= - 68.89ni÷areEd
= 3.51 m
; .
Rd =3.
5 m [ up ]
b) 82=8,
to at
One = 8.3ns tf9 .
8mg) at
Org - 8.3 ;D= -9.8mg ,
1st
-
8.3M¥= Attae
85 s = at
Read 1.6 ( pg 40 . 4D
# 2pg . 42 .
