1-D Kinematics
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Definitions:
One-dimension: straight line, to the left or to the right, up or down, east or west, etc.
Kinematics: the study of motion using words, numbers, graphs and equations
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Scalars vs. Vectors
There are a lot of different mathematical quantities used in physics. Examples of these include acceleration, velocity, speed, force, work, and power. These different quantities are often described as being either "scalar" or "vector" quantities.
Scalar - A quantity that has only a magnitude (number or value)
Vector - A quantity that has both a magnitude and a direction
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Conceptual Example #1: Scalar & Vectors
Which of the following are scalars and which are vectors?
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Scalar
Vector
Scalar
Scalar
Vector (the negative implies a direction. Directions include down, left, south, west, etc.)
Scalars and Vectors
In Physics you will often see a negative sign. This will often imply a direction. Unless otherwise stated a “-” implies left, down, South, West, etc.
Example: Jessica pushed a box with a force of -50 Newtons, would look like the following:
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Conceptual Example #2: Scalar & Velocity
Which of the following are examples of positive directions?
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Conceptual Example #3: Scalar & Velocity
Which of the following are examples of negative directions?
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Conceptual Example #4: Scalar & Velocity
Laura is pushing the box with a force of 40 Newtons. �Melissa is pushing on the box with a force of -20 Newtons. �From looking at the picture below, which figure is Laura and which figure is Melissa?
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Laura
Melissa