Speed/Velocity & Distance/Displacement

• What are the two types of quantities discussed?

  Scalar and vector
• What is a scalar quantity?

  It only has magnitude
• What is a vector quantity?

  It has both magnitude and direction
• Is speed a scalar or vector quantity?


  Scalar quantity
• Give an example of speed.

  A person running at 4 m/s
• Is velocity a scalar or vector quantity?

  Vector quantity
• Give an example of velocity.

  A person cycling 6 m/s east
• Why is it common to confuse speed and velocity?

  Both are related to motion but differ in direction
• What is distance considered as?

  Scalar quantity
• What is displacement considered as?

  Vector quantity
• Provide an example of distance.

  10 meters
• Provide an example of displacement.

  A person running 40 meters east
• How do you calculate speed?

  • Speed = Distance / Time
  • Example: 550 meters / 10 seconds = 55 m/s
• What is the speed of a train that crosses a 550-meter bridge in 10 seconds?

  $55 \text{ m/s}$
• How do you calculate velocity?

  • Velocity = Displacement / Time
  • Example: 550 meters east / 10 seconds = 55 m/s east
• If a train travels 550 meters east in 10 seconds, what is its velocity?

  $55 \text{ m/s east}$
• What does the letter 's' represent in the velocity equation?

  Displacement
• What does the letter 'd' represent in the speed equation?

  Distance
• What does the letter 't' represent in both equations?

  Time
• Why do people often use the velocity equation incorrectly?

  They may not have a direction
• What is a benefit of using velocity?

  It can represent negative values
• What is average speed?

  Total distance divided by total time
• What is average velocity?

  Total displacement divided by total time
• What are typical walking, running, and cycling speeds in m/s?

  • Walking: 1.5 m/s
  • Running: 3 m/s
  • Cycling: 6 m/s
• What is the speed of a car on the main road?

  25 m/s
• What is the speed of a fast train?

  55 m/s
• What is the speed of planes?

  Exceeds 250 m/s
• What is the speed of sound waves in air?

  330 m/s
• How does the speed of sound change in different mediums?

  It varies depending on the medium
• What factors can affect wind speed?

  Temperature, pressure, and structures
• What are the differences between speed and velocity?

  • Speed: Scalar, only magnitude
  • Velocity: Vector, magnitude and direction
• What are the differences between distance and displacement?

  • Distance: Scalar, only magnitude
  • Displacement: Vector, magnitude and direction