SPH 3U Grade 11 U Physics
• This lesson will teach you how to draw and analyze
acceleration time graphs.
• Many aspects of graphical analysis will also be covered
SPH 3U Grade 11 U Physics
What are we going to cover today?
By the end of this lesson,
you will be able to:
Uniform motion a-t
graphs
Non -uniform
motion a-t graphs
Moving from one
graph to another
Homework
Would you believe me if I told you that if you
walked straight at a wall that you would
never actually get to the wall?
the sum of an infinite number of little rectangles
summing the area under a curve.
acceleration
Describe the “set” of motion patterns in 2 – 5 words
7.0
accel (m/s2 [D])
SPH 3U Grade 11 U Physics
Uniform motion = zero
acceleration
6.0
5.0
4.0
3.0
2.0
1.0
1.0 2.0 3.0 4.0 5.0 6.0 7.0
time (s)
SPH 3U Grade 11 U Physics
The slope of an a-t graph is called jerk, which is
defined as the rate of change of acceleration
The area under an a-t
graph is Dv
In this course we will only be
studying motion with a jerk of
zero.
i.e. a-t graphs with slope = zero
14
accel (m/s2 [D])
SPH 3U Grade 11 U Physics
Non-uniform motion
indicates that the
object is accelerating
12
10.
8.0
6.0
4.0
2.0
1.0 2.0 3.0 4.0 5.0 6.0 7.0
time (s)
accel (m/s2 [D])
SPH 3U Grade 11 U Physics
area  10. m/s2 [D]  5.0 s
 50. m/s [D]
14
12
10.
 Dv16s  50. m/s [D]
8.0
6.0
4.0
area = Dv
2.0
1.0 2.0 3.0 4.0 5.0 6.0 7.0
time (s)
14
accel (m/s2 [D])
SPH 3U Grade 11 U Physics
Determine a v-t and d-t graph for the a-t graph below
12
10.
8.0
6.0
4.0
2.0
1.0 2.0 3.0 4.0 5.0 6.0 7.0
time (s)
SPH 3U Grade 11 U Physics
Sol’n: This is a graph of non-uniform motion
non-uniform motion is a diagonal straight line
on a v-t graph with slope equal to a
So, the v-t graph would have slope equal to +10
60.
velocity (m/s [D])
SPH 3U Grade 11 U Physics
70.
50.
40.
30.
20.
10.
1.0
2.0
3.0
4.0
5.0
6.0
time (s)
7.0
velocity (m/s [D])
SPH 3U Grade 11 U Physics
To determine the d-t graph we use the area under
the v-t graph to calculate the displacement.
70.
time (s)
Displacement
(m [D])
60.
0.0
0.0
1.0
5.0
2.0
20.0
40.
3.0
45.0
30.
4.0
80.0
50.
20.
10.
1.0 2.0 3.0 4.0 5.0 6.0 7.0
time (s)
70.
60.
Position (m [D])
SPH 3U Grade 11 U Physics
80.
50.
40.
30.
20.
10.
1.0
2.0
3.0
4.0
5.0
6.0 7.0
time (s)
SPH 3U Grade 11 U Physics
1. The area under an a-t graph is
a.
b.
c.
d.
e.
position
displacement
Dv
acceleration
jerk
SMART Response Question
SPH 3U Grade 11 U Physics
2. The slope of an a-t graph is
a.
b.
c.
d.
e.
position
displacement
Dv
acceleration
jerk
https://www.youtube.com/watch?v=kpNPw4H6_tU
SPH 3U Grade 11 U Physics
3. Which a-t graph depicts uniform motion?
a.
b.
c.
The End
d.
SPH 3U Grade 11 U Physics
4. Which a-t graph depicts non-uniform motion,
positive acceleration?
a.
b.
c.
SMART Response Question
d.
SPH 3U Grade 11 U Physics
5. Which v-t graph depicts uniform motion?
a.
b.
c.
SMART Response Question
d.
SPH 3U Grade 11 U Physics
6. Which d-t graph depicts non-uniform motion?
a.
b.
c.
SMART Response Question
d.
SPH 3U Grade 11 U Physics
Read pgs 41 - 46
Questions: All concept and practice questions