describing motion

• What are the two types of quantities?

  Scalar and vector
• What defines a scalar quantity?

  It has only magnitude
• Why is distance considered a scalar quantity?

  It only contains magnitude, not direction
• What defines a vector quantity?

  It has both magnitude and direction
• How is velocity described as a vector quantity?

  It includes both speed and direction
• How does displacement differ from distance?

  Displacement includes direction, distance does not
• What is the difference between distance and displacement?

  Distance measures how far, displacement includes direction
• In a 300 m race, what is the distance travelled?

  300 m
• What does displacement measure in a race?

  How far from the starting position
• What is the definition of mass?

  Quantity with magnitude only
• How does weight differ from mass?

  Weight has magnitude and direction
• How does weight change in outer space?

  It varies with distance from Earth
• What are commonly confused pairs of scalars and vectors?

  • Distance and displacement
  • Speed and velocity
  • Weight and mass
• What is speed defined as?

  Distance travelled every second
• Why is speed considered a scalar quantity?

  It only contains magnitude
• What is the formula for calculating speed?

  Speed = distance / time
• How can average speed be calculated?

  By using total distance and total time
• How do you use formula triangles in physics?

  • Cover the quantity to calculate
  • Identify multiplication or division
  • Rearrange the equation accordingly
• How do you convert hours into seconds?

  Multiply by 3600
• What does a distance-time graph show?

  Distance varies over time
• What does a straight line on a distance-time graph indicate?

  Constant speed
• What does a steep slope on a distance-time graph represent?

  Large speed
• What does a flat line on a distance-time graph indicate?

  Object is stationary
• How is changing speed represented on a distance-time graph?

  By a curve
• What does an increasing slope on a distance-time graph indicate?

  Object is accelerating
• What does a decreasing slope on a distance-time graph indicate?

  Object is decelerating
• How can speed be calculated from a distance-time graph?

  By calculating the gradient
• What is the formula for average acceleration?

  a = Δv / t
• What does acceleration describe?

  Rate of change of velocity
• How is change in velocity calculated?

  Final velocity minus initial velocity
• What indicates positive acceleration?

  Object is speeding up
• What indicates negative acceleration?

  Object is slowing down
• How do you interpret a negative deceleration value?

  Indicates the object is slowing down
• What is the acceleration due to gravity?

  Acceleration of objects in freefall
• What are the key points about freefall?

  • All objects fall with the same acceleration
  • This acceleration is due to gravity
• What is the initial velocity of the train?

  50 m/s
• What is the final velocity of the train?

  42 m/s
• How is the change in velocity calculated?

  Final velocity minus initial velocity
• What is the change in velocity for the train?

  −8 m/s
• What is the time taken for the train's deceleration?

  30 s