Describing Motion

• What is distance a measure of?

  Distance is a measure of how far an object travels
• What type of quantity is distance?

  Distance is a scalar quantity
• How far did the athletes run in the example provided?

  The athletes ran a total distance of 300 m
• What does displacement measure?

  Displacement measures how far something is from its starting position, along with its direction
• What type of quantity is displacement?

  Displacement is a vector quantity

  
• If the athletes ran a total distance of 300 m but ended up 100 m from where they started, what is their displacement?

  Their displacement is 100 m to the right
• What would be the final displacement if the athletes had run a full 400 m?

  The final displacement would be zero
• What is speed defined as?

  Speed is the distance an object travels every second
• What type of quantity is speed?

  Speed is a scalar quantity
• How is average speed calculated?

  Average speed is calculated using the equation: speed = distance/time

  
• What are the units for speed?

  Speed is measured in metres per second, m/s
• What is an example of average speed for a hiker?

  An average speed of a hiker might be 2.0 m/s
• What is an example of average speed for a bumblebee?

  A bumblebee can have average speeds of up to 4.5 m/s
• What does average speed represent?

  Average speed represents the mean speed of a moving object

  
• Why might average speed differ from instantaneous speed?

  Because the speed of an object can change at different moments
• What is non-uniform motion?

  Non-uniform motion refers to motion that is changing
• What can changing motion involve?

  Changing motion can involve changing speed, direction, or both
• What is a common example of non-uniform motion?

  Cars speeding up and slowing down throughout a journey
• How can non-uniform motion be simplified for students?

  By explaining that non-uniform means motion that doesn’t stay the same
• What factors affect typical speeds of a person walking?

  • Age
  • Terrain
  • Fitness
  • Distance
• What is a typical speed for a person walking?

  About 1.5 m/s
• What is a typical speed for a plane?

  A typical speed for a plane is around 250 m/s
• What is the speed of sound in air?

  The speed of sound in air is 330 m/s
• What is the speed of sound in seawater?

  The speed of sound in seawater is typically around 1500 m/s
• How can speed be measured accurately?

  By timing how long it takes to travel a known distance

  
• What equipment can be used to measure distance and time?

  A metre rule and a timer
• What is a more appropriate tool for measuring long distances?

  A trundle wheel
• How do light gates measure time accurately?

  Light gates start a timer when an object passes through them

  
• What does a single light gate measure?

  A single light gate measures the speed of an object as it passes through

  
• What is the equation for calculating speed?

  Speed = distance/time

  
• How do you calculate the distance traveled by a plane flying at 250 m/s for 2 hours?

  Distance = speed × time = 250 m/s × 7200 s = 1,800,000 m
• What is average speed for non-uniform motion?

  Average speed is calculated using total distance divided by time taken

  
• What is Florence Griffith Joyner's average speed during her 100 m world record race?

  Average speed = 100 m ÷ 10.49 s = 9.53 m/s
• How does velocity differ from speed?

  Velocity describes both magnitude and direction, while speed only describes magnitude
• Why is velocity considered a vector quantity?

  Because it describes both magnitude and direction

  
• What happens to velocity when an object moves in a circular path?

  The velocity is always changing due to the change in direction
• What is the speed of the International Space Station?

  The International Space Station travels at a constant speed of about 7660 m/s

  
• What is the difference between vector and scalar quantities?

  • Scalar quantities describe magnitude only (e.g., temperature)
  • Vector quantities describe both magnitude and direction (e.g., force)

  
• What happens to velocity in circular motion?

  Velocity changes because the direction of travel is always changing
• What information can be obtained from a distance-time graph?

  • Shows how distance varies over time
  • Indicates constant speed
  • The slope represents the magnitude of speed