Transcript Vectors

Vectors
Vector and Scalar quantities
• Scalar quantities have size or magnitude,
but a direction is not specified.
(temperature, mass, speed, etc.)
• Vector quantities have magnitude and a
specific direction (velocity, acceleration,
etc.)
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Arrows Represent Vectors
• Vector quantities are represented by
drawing arrows.
• The arrows are drawn to represent
magnitude (size of arrow) and direction
(position of arrow).
The Resultant Vector
The resultant is a vector that represents
the sum of two or more vectors.
Finding the Resultant
• Align the vector arrow tip to tail.
Resultant
Resultant
One way to find a resultant could be to draw the
situation to scale on paper (such as 50 m = 1 cm).
Measuring the length of the vector pointing from the
tail of the first vector to the head the second
vector, and then,
multiplying by the
scale .
For example if
line (c) is 3.0 cm
the distance would
be 150 meters.
This is the
displacement.
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An example of the head-to-tail
method of vector addition
Using Pythagorean theorem to find
a resultants magnitude.
A toy car is moving directly across a moving
walkway. As the car moves in the y direction,
the walkway moves in the x direction.
• We can look at the diagram as a triangle.
Therefore we can solve this by using the
Pythagorean theorem.
b
a
c
Use the tangent function to find the
direction of the resultant.
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Pythagorean and Trigonometric
Equations
soh cah toa
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Other helpful right triangle functions
besides tangent
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