P1 forces and motion

• What is a scalar quantity?

  A magnitude described by a single value
• Give two examples of scalar quantities.

  Distance and speed
• How is a scalar quantity defined?

  A scalar quantity has only magnitude
• What are two examples of vector quantities?

  Force and velocity
• What is a vector quantity?

  A quantity with both magnitude and direction
• What property of a distance-time graph is used to calculate speed?

  Gradient (or slope)
• How can you determine the state of motion from distance-time graphs?

  • Constant speed: Straight line with positive slope
  • At rest: Horizontal line
  • Accelerating: Curved line upward
• What is the equation linking distance moved, time taken, and average speed?

  Average speed = Distance / Time
• What is acceleration?

  Change in velocity per unit of time
• What is the SI unit of acceleration?

  m/s²
• What is the equation linking acceleration, change in velocity, and time taken?

  Acceleration = Change in velocity / Time
• What property of a velocity-time graph is used to calculate acceleration?

  Gradient (slope)
• What property of a velocity-time graph is used to calculate distance travelled?

  Area under the graph
• How can you determine the state of motion from velocity-time graphs?

  • Constant speed: Horizontal line
  • Accelerating: Straight line with positive slope
  • Decelerating: Straight line with negative slope
• What is the equation linking final speed, initial speed, acceleration, and distance travelled?

  Final speed = Initial speed + (Acceleration * Distance)
• What are the types of forces acting on objects?

  • Weight
  • Air Resistance (Drag)
• Name two types of forces that always oppose motion.

  Friction and Air Resistance
• Which type of force holds planets around the Sun?

  Gravitational Force
• Which type of force holds electrons around the nucleus?

  Electrostatic Force
• How can a force affect the body it is applied on?

  • Change the shape (extension/compression)
  • Change the speed
  • Change the direction of motion
• What is the result of applying a force to an object?

  It can change the object's motion
• What type of force holds planets around the Sun?

  Gravitational Force
• What type of force holds electrons around the nucleus?

  Electrostatic Force
• What are the ways a force can affect a body?

  • Change the shape of the object
  • Change the speed of the object
  • Change the direction of the object
• What is the resultant force for an object with 5N to the right?

  5N to right
• What is the resultant force for an object with 13N downwards?

  13N downwards
• What is the resultant force for an object that is balanced?

  0N (balanced)
• What is the magnitude of the resultant force if it is 10N?


  10N
• What is the magnitude of the resultant force if it is 45N?


  45N
• What is the equation linking unbalanced force, mass, and acceleration?

  F = m x a
• What is the equation linking mass, weight, and gravitational acceleration?

  W = mg
• What is the relationship between stopping distance, braking distance, and thinking distance of a car?

  Stopping Dist. = Thinking Dist. + Braking Dist.
• What are the factors that affect the stopping distance of a car?

  • Reaction time
  • Weather conditions
  • Initial speed
  • Driver’s conditions
  • Road conditions
  • Mass of the car
  • Tire conditions
• What are two factors that affect air resistance acting on a falling object?

  Surface Area and Speed
• How does a falling object reach terminal velocity?

  • Falls under weight's effect, accelerating with g
  • Air resistance increases, reducing resultant force
  • When air resistance equals weight, forces balance
  • Resultant force = 0, acceleration = 0, reaches terminal velocity
• What does obeying Hooke’s Law mean?

  Extension is directly proportional to force applied
• What is the difference between elastic and plastic behavior?

  • Elastic: Recovers original shape after force removal
  • Plastic: Permanent deformation after force removal