Motion in One Dimension

1
Motion in One Dimension

• Kinematics

2
Dynamics vs. Kinematics

• Dynamics motion related to cause (force)
• Kinematics describes motion mathematically
  without regard to cause

3
Frame of Reference

• Specify an origin
• For 1-D motion the coordinate system is linear

4
Time and Space

• Instant particular point in time
• Interval difference between two instants

• Position particular point in space
• Displacement difference between two positions

5
Vectors vs. Scalars

• Vectors indicate magnitude and direction
• Boldfaced and/or vector sign

Displacement
Velocity
Acceleration

• Scalars indicate magnitude only

Distance
Speed
Magnitude of acceleration
6
Displacement is a Vector
Fig. 2.2, p. 25
For 1-D, vector nature is indicated by or - sign
7
Displacement

• Change in position is called displacement
• The sign tells us if its towards positive or
  negative values

8
Average Velocity

• Displacement divided by time interval
• The sign tells us if its moving toward positive
  or negative values

9
Instantaneous Velocity

• The average velocity when the time interval
  approaches zero
• It is the slope of the line of a position versus
  time graph

10
Average Acceleration

• The change in velocity over a time interval

11
Instantaneous Acceleration

• The average acceleration when the time interval
  approaches zero
• It is the slope of a velocity versus time graph

12
Types of Motion

• Uniform Motion v constant, a 0
• Nonuniform Motion
• Uniform acceleration a constant
• Nonuniform acceleration a is not constant