Force and motion

• What is a scalar quantity?

  A quantity which only has magnitude
• Give three examples of scalar quantities.

  Distance, speed, mass
• What is a vector quantity?

  A quantity which has magnitude and direction
• Give three examples of vector quantities.

  Displacement, velocity, acceleration
• Why is velocity different from speed?

  Velocity has a direction
• What is the equation linking speed, distance, and time?

  Speed = Distance / Time
• What does a flat line on a distance-time graph represent?

  A stationary object
• How do you determine the speed of an object from a distance-time graph?

  Gradient of the graph
• What does a steeper line represent on a distance-time graph?

  Faster speed
• What is the equation linking acceleration, velocity, and time?

  Acceleration = Change in velocity / Time
• What does a flat line on a velocity-time graph represent?

  Constant speed
• How is acceleration determined on a velocity-time graph?

  Gradient of the graph
• How is total distance travelled determined on a velocity-time graph?

  Area under the graph
• What is the value for acceleration due to gravity on Earth?

  1. 8 m/s²
• What is Newton's first law?

  An object remains at constant speed if no force acts
• What is Newton's second law?

  Force = Mass x Acceleration
• Define weight.

  Weight is the force due to gravity
• What happens to the weight of an object if gravitational field strength increases?

  The weight increases
• How can you experimentally determine the relationship between force, mass, and acceleration?

  • Attach a mass to a trolley
  • Measure distance for trolley to travel
  • Release mass and record time taken
  • Calculate speed, then acceleration
  • Calculate force using mass and gravity
  • Repeat for different masses
  • Plot a graph of force against acceleration
• What is Newton's third law?

  If A exerts force on B, B exerts equal force on A