Chap.%203:%20Kinematics%20in%20Two%20or%20Three%20Dimensions:%20Vectors

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Chap. 3 Kinematics in Two or Three Dimensions
Vectors
Study guide is posted online (Homework page)
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Problem 11

11.(II) (a) Given the vectors and in
problem 10. determine . (b)Determine
without using your answer in (a). Then compare
your results and see if they are opposite.
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Problem 16
16. (III) You are given a vector in the xy plane
that has a magnitude of 90.0 units and a y
component of -55units (a) What are the two
possibilities for its x component? (b) Assuming
the x component is known to be positive, specify
the vector which, if you add it to the original
one, would give a resultant vector that is 80.0
units long and points entirely in the -x
direction.
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Adding Vectors by Components
Example 3-2 Mail carriers displacement. A rural
mail carrier leaves the post office and drives
22.0 km in a northerly direction. She then drives
in a direction 60.0 south of east for 47.0 km.
What is her displacement from the post office?
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Vector Kinematics
In two or three dimensions, the displacement is a
vector
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Vector Kinematics
As ?t and ?r become smaller and smaller, the
average velocity approaches the instantaneous
velocity.
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Vector Kinematics
The instantaneous acceleration is in the
direction of? 2 1, and is given by
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Vector Kinematics
Using unit vectors to write velocity and
acceleration,
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Problem 17

• (I) The position of a particular particle as a
  function of time is given by
• Determine the particles velocity and
  acceleration as a function of time.

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Example 3-5 Position given as a function of time
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