the kinematic equations
TRANSCRIPT
![Page 1: The Kinematic Equations](https://reader031.vdocument.in/reader031/viewer/2022012102/6169fe5911a7b741a34da47c/html5/thumbnails/1.jpg)
The Kinematic EquationsIB PHYSICS | MOTION
![Page 2: The Kinematic Equations](https://reader031.vdocument.in/reader031/viewer/2022012102/6169fe5911a7b741a34da47c/html5/thumbnails/2.jpg)
Motion Variables
Displacement Initial Velocity Final Velocity Acceleration Time
Whenever we are describing the motion of an accelerating object, there are five variables that we need to take into account
Note: The variables used in IB Physics vary slightly from other nomenclature standards
s tu v a
![Page 3: The Kinematic Equations](https://reader031.vdocument.in/reader031/viewer/2022012102/6169fe5911a7b741a34da47c/html5/thumbnails/3.jpg)
Calculating Acceleration
πππππππππ‘πππ =πππππ π£ππππππ‘π¦ β ππππ‘πππ π£ππππππ‘π¦
πβππππ ππ π‘πππ
Sym
bo
lsU
nit
s
=
= a v - ut
ms-2 ms-1 ms-1
s-
![Page 4: The Kinematic Equations](https://reader031.vdocument.in/reader031/viewer/2022012102/6169fe5911a7b741a34da47c/html5/thumbnails/4.jpg)
Think about this unitβ¦
m/s/sm/s2
m s-2
π =π£ β π’
π‘
![Page 5: The Kinematic Equations](https://reader031.vdocument.in/reader031/viewer/2022012102/6169fe5911a7b741a34da47c/html5/thumbnails/5.jpg)
Try This | 1
What is the acceleration of a car that accelerates from 15 m s-1 to 35 m s-1 in 10 seconds?
π’
π£
π
π‘
π =π£ β π’
π‘
π = ππ¦π¬βπ
15 ms-1
35 ms-1
10 s
?
=35 β 15
10
![Page 6: The Kinematic Equations](https://reader031.vdocument.in/reader031/viewer/2022012102/6169fe5911a7b741a34da47c/html5/thumbnails/6.jpg)
Try This | 2
Find the average acceleration of a northbound train that slows down from 12 m s-1 to a complete stop in 8 sec *Tip: You can get a negative value!
π’
π£
π
π‘
π =π£ β π’
π‘
π = βπ. π π¦π¬βπ
12 ms-1
0 ms-1
8 s
?
=0 β 12
8
![Page 7: The Kinematic Equations](https://reader031.vdocument.in/reader031/viewer/2022012102/6169fe5911a7b741a34da47c/html5/thumbnails/7.jpg)
Solve for v
π =π£ β π’
π‘
π£ = π’ + ππ‘
![Page 8: The Kinematic Equations](https://reader031.vdocument.in/reader031/viewer/2022012102/6169fe5911a7b741a34da47c/html5/thumbnails/8.jpg)
Physics Data Booklet
![Page 9: The Kinematic Equations](https://reader031.vdocument.in/reader031/viewer/2022012102/6169fe5911a7b741a34da47c/html5/thumbnails/9.jpg)
How far have I gone?V
elo
city
(m
s-1
)
Time (s)
20
40
60
80
100
2 4 6 8 101 3 5 7 9 11 12
120
10 s
80 m s-1
π = π£π‘ = 80 m sβ1 10 s = 800 m
ππππ π’ππππ ππππβ = 80 m sβ1 10 s = 800 m
![Page 10: The Kinematic Equations](https://reader031.vdocument.in/reader031/viewer/2022012102/6169fe5911a7b741a34da47c/html5/thumbnails/10.jpg)
Use the graphs to tell you MORE!Sl
op
eA
rea Un
der C
urve
Displacement vs Time
Velocity vs Time
Slo
pe
Velocity vs Time
Velocity
Acceleration
Displacement
![Page 11: The Kinematic Equations](https://reader031.vdocument.in/reader031/viewer/2022012102/6169fe5911a7b741a34da47c/html5/thumbnails/11.jpg)
How far have I gone?V
elo
city
(m
s-1
)
Time (s)
20
40
60
80
100
2 4 6 8 101 3 5 7 9 11 12
120 ππππ π’ππππ ππππβ = 60 m sβ1 8 s = 480 m
π΄π£πππππ πππππππ‘π¦ =π£ + π’
2
π =π£ + π’
2Γ π‘
![Page 12: The Kinematic Equations](https://reader031.vdocument.in/reader031/viewer/2022012102/6169fe5911a7b741a34da47c/html5/thumbnails/12.jpg)
Physics Data Booklet
![Page 13: The Kinematic Equations](https://reader031.vdocument.in/reader031/viewer/2022012102/6169fe5911a7b741a34da47c/html5/thumbnails/13.jpg)
What if I donβt know v?
π£ = π’ + ππ‘π = π£+π’ π‘2
π = π’+ππ‘+π’ π‘2
π = 2π’π‘+ππ‘2
2π = π’π‘+
12ππ‘2
= 2π’+ππ‘ π‘2
![Page 14: The Kinematic Equations](https://reader031.vdocument.in/reader031/viewer/2022012102/6169fe5911a7b741a34da47c/html5/thumbnails/14.jpg)
Physics Data Booklet
![Page 15: The Kinematic Equations](https://reader031.vdocument.in/reader031/viewer/2022012102/6169fe5911a7b741a34da47c/html5/thumbnails/15.jpg)
One more equation
π£2 = π’2 + 2ππ
![Page 16: The Kinematic Equations](https://reader031.vdocument.in/reader031/viewer/2022012102/6169fe5911a7b741a34da47c/html5/thumbnails/16.jpg)
Equations
π£ = π’ + ππ‘
π = π’π‘ + 12ππ‘2
π£2 = π’2 + 2ππ
π = π£+π’ π‘2
m m s-1 m s-1 m s-2 s
π’ π£ π π‘
π π’ π π‘
π π’ π£ π
π π’ π£ π‘
![Page 17: The Kinematic Equations](https://reader031.vdocument.in/reader031/viewer/2022012102/6169fe5911a7b741a34da47c/html5/thumbnails/17.jpg)
Try This | 3
π
π’
π£
π
π‘
You speed up with a uniform acceleration from 0 m/s to 30 m/s in 5 seconds. How far have you gone?
π = 30+0 (5)2
0 m s-1
30 m s-1
5 s
?
------
= πππ¦
![Page 18: The Kinematic Equations](https://reader031.vdocument.in/reader031/viewer/2022012102/6169fe5911a7b741a34da47c/html5/thumbnails/18.jpg)
Try This | 4
π
π’
π£
π
π‘
If a plane on a runway is accelerating at 4.8 m s-2 for 15 seconds before taking off, how long should the runway be?
π = π’π‘ + 12ππ‘2
= (0)(15) + 12(4.8)(15)2
π = 540 m
0 m s-1
------
15 s
?
4.8 m s-2
![Page 19: The Kinematic Equations](https://reader031.vdocument.in/reader031/viewer/2022012102/6169fe5911a7b741a34da47c/html5/thumbnails/19.jpg)
Try This | 5
π
π’
π£
π
π‘
A driver slams on the brakes and skids for 3 seconds before coming to a stop. You go and measure that the skid marks show a deceleration over 9 m. What was the initial speed of the car?
π = π£+π’ π‘2
π’ = 2π π‘β π£
π’ = 6 m sβ1
?
0 m s-1
3 s
9 m
-----= 2(9)(3)
β 0
![Page 20: The Kinematic Equations](https://reader031.vdocument.in/reader031/viewer/2022012102/6169fe5911a7b741a34da47c/html5/thumbnails/20.jpg)
Lesson Takeaways
β I can identify the 5 primary variables of motion
β I can identify the proper kinematic equation to use for a
problem that is presented
β I can rearrange to solve for the unknown variable
β I can calculate for an unknown