Displacement

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Slides
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Displacement
Vectors
Kinematics
Graphs
Energy
Power
Springs
Shadows
Field of Vision
Colors
Concave mirrors
Convex mirrors
Refraction
Lenses
Optical Power
Slides Minutes
9
27
13
39
13
39
10
30
10
30
5
15
4
12
3
9
7
21
3
9
7
21
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12
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15
10
30
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18
Free Body Diagrams
A free body diagram is a pictorial representation of an
object used to study the forces acting on a system.
A free body diagram shows
only the information required
by the problem under study.
Ending point
Distance is a scalar. (It has no direction)
Displacement is a vector. (It has direction)
Starting point
Ao
Displacement is the straight line
directly from the starting point
to the ending point.
Remember: Displacement has magnitude and direction.
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Displacement Slide:
An object travels the following distances:
III
II
9 m [E], 6 m [N], 4 m [W] and 2 m [S]
Which of the vectors on the right represents
the displacement of the object?
A)
B)
C)
D)
I
II
III
IV
I
IV
4 m [W]
2 m [S]
6 m [N]
Displacement
9 m [E]
Not drawn to scale
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Displacement Slide:
Riding her bike, Stefania traveled the following distance from
point-A to point-D:
AB = 4.00km North
BC = 11.3 km [S 45 E]
CD = 8.00 km West
Determine Stefania’s displacement.
A) 4.00 km North
B) 4.00 km South
C) 23.3 km North
D) 23.3 km South
E) 0
Note
BD = CD = 8.00 km
and
BA = AD = 4.00 km
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Displacement Slide:
The graph below represents the velocity of a butterfly
as it flies across a field for 20 seconds.
+235 m (forward)
-90 m (backward)
What is the displacement of the butterfly from the 4 th to the 20 th s?
A) 365 m
B) 325 m
C) 185 m
D) 145 m
Displacement Slide:
To go from his house to four of his friends, James must travel
in different directions as listed below:
NOTE
Ann: 4.8 km [N] , 3.2 km [W]
We need only consider
Bill:
20 km [N] , 15 km [S]
the magnitude and not
Chris: 3 km [N] , 7 km [S 45o E]
the direction.
Don: 3.5 km [S] , 1 km [E] , 2 km [S]
Which friend has the greatest displacement from James’ house?
A) Ann
Ann:
5.8 km
Bill:
5 km
B) Bill
Chris: 5.4 km
C) Chris
Don:
2.5 km
D) Don
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Displacement Slide:
0
20 km E
Displacement is a vector from the starting
point directly to the ending point.
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Displacement Slide:
1
2
3
4
5
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Displacement Slide:
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2 km
Ending point
Displacement Slide:
Starting point
Displacement Slide:
The graph below represents the motion of an automobile as it moves northward.
Determine the displacement of the automobile.
Right represents North
Forward
Remember:
displacement is the
straight
line
from
the
Displacement
starting point to the
ending point.
The
forward velocity
displacement
is the
under
the curve
above
the x-axis
Positive
(above
thearea
x-axis)
means
going
forward.
NOTE
The area
fromvelocity
the line
to
the
x-axis
forward
Since
plotted
The backward
displacement
is is
the
area
aboverepresents
the curve below
the x-axis
distance
since
it has
versus time,
the
areaa positive value.
Negative to
velocity
(below
the x-axis) means going backward.
the x-axis
represents
Note
that represents
for the problem,
the time
The areathe
from
the linetraveled.
to the
x-axis
backward
distance
the ending
point (t = 20 s).
distance since itstops
has aat
negative
value.
Forward
Backward
However, according to the graph, the
Ending
Starting
automobile continues to accelerate
point
point
160 m North
backwards.
Click
Click
… and good luck!
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