prelim

• What are the two types of quantities in physics?

  Scalar and vector quantities
• What do scalar quantities represent?

  They represent size or magnitude only
• Give examples of scalar quantities.

  Speed, distance, time, mass, energy
• What do vector quantities represent?

  They represent size and direction
• Give examples of vector quantities.

  Velocity, displacement, acceleration
• How are vector quantities visually represented?

  By arrows indicating magnitude and direction
• What happens when a force is applied in opposite directions?

  It results in positive and negative forces
• How can the motion of an object be described?

  By speed, direction, and speed change
• What is the symbol for distance?


  d
• What does displacement measure?

  Straight-line distance and direction
• If you walk 6 m north and then 6 m south, what is your displacement?

  0 m
• What is speed?

  A scalar quantity indicating how fast
• How does velocity differ from speed?

  Velocity includes direction, speed does not
• What is an example of constant speed with changing velocity?

  A car moving in a circle
• What is acceleration?

  Rate of change of velocity
• How can acceleration be measured in a practical experiment?

  Using light gates and a trolley on a ramp
• What is the formula for acceleration?

  Change in velocity divided by time
• What happens to acceleration if the ramp is steeper?

  Acceleration will increase
• What happens to acceleration if the trolley is heavier?

  Acceleration will not change
• What is the equation for uniform acceleration problems?

  v² = u² + 2as
• Calculate the acceleration if a trolley's speed changes from $15 \text{ m/s}$ to $25 \text{ m/s}$ over $25 \text{ m}$.


  $8 \text{ m/s}^2$
• What is the significance of a gradient on a distance-time graph?

  It indicates speed of the object
• What does a positive gradient on a velocity-time graph indicate?

  Acceleration is occurring
• What does a negative gradient on a velocity-time graph indicate?

  Deceleration is occurring
• What is a force?

  Anything that causes a change in motion
• What are contact forces?


  Forces that require physical contact
• What are non-contact forces?

  Forces that act over a distance
• What is a resultant force?

  The overall force acting on an object
• What happens if all forces are balanced?

  The resultant force is zero
• What happens if forces are unbalanced?

  The object will accelerate
• How does a greater resultant force affect acceleration?

  It leads to higher acceleration
• What does Newton's First Law state?

  No resultant force means no change in motion
• What does Newton's Second Law state?

  An unbalanced force causes acceleration
• What does Newton's Third Law state?

  Equal and opposite forces act on objects
• How can weight be calculated?

  Weight = mass × gravitational field strength
• What is the weight of a 5 kg mass on Earth?

  $49 \text{ N}$
• What is the weight of a 5 kg mass on the Moon?

  $8 \text{ N}$
• What is terminal velocity?

  The constant speed of a falling object
• What factors affect terminal velocity?

  Shape and area of the object
• What is work done?

  When a force moves an object