Paper 1

• Units to convert between multiples and submultiples

  • Giga
  • Mega
  • Kilo
  • Centi
  • Milli
  • Micro
  • Nano
• You need to know the standard SI units for time, distance, weight, mass, frequency, and speed
• Converting between units


  1. Identify the difference in orders of magnitude between the units

  2. Multiply or divide by the appropriate power of 10
• Equations for speed, distance, and time

  1. D = S x T

  2. S = D / T

  3. T = D / S
• Constant velocity is shown by the horizontal part of a velocity-time graph
• Distance travelled is given by the area under a velocity-time graph
• Average speed = Distance / Time
• Acceleration = Change in velocity / Time
• Weight = Mass x Gravitational field strength
• Weight


  Force exerted on an object due to gravity, measured in Newtons
• Mass


  Amount of matter in an object, measured in kilograms
• Mass does not change with location, but weight does due to changes in gravitational field strength
• Forces can change an object's speed, direction, or shape
• Mass


  The amount of matter in an object
• Weight


  The force acting downwards on an object due to gravity
• Gravitational field strength


  The force of gravity per unit mass at a given location
• On Earth


  Gravitational field strength is approximately 10 N/kg
• On the Moon


  Gravitational field strength is only 1.6 N/kg
• Your weight on the Moon is only 80 Newtons, even though your mass is the same
• In everyday life, we talk about how much we "weigh" when we are actually discussing our mass
• Weight


  Mass x Gravitational field strength
• Force


  • Can change an object's speed, direction, or shape
• Types of force


  • Contact forces
  • Non-contact forces
• Normal reaction force


  Force perpendicular to the surface an object is resting on
• Friction


  Force between two surfaces sliding past each other
• Air resistance/Drag


  Force on an object moving through air, increases with speed
• Magnetic force


  Force experienced by magnetic materials in a magnetic field
• Electrostatic force


  Force experienced by charged particles in an electric field
• Gravitational force


  Force between masses due to gravity
• Upthrust


  Upward force on an object immersed in a fluid
• Nuclear force


  Strong attractive force between protons and neutrons in a nucleus
• Force is measured in Newtons
• Force diagram


  Visual representation of forces acting on an object
• Balanced forces


  Forces acting in opposite directions, equal in size
• Unbalanced forces


  Forces acting in opposite directions, unequal in size
• Terminal velocity


  Constant speed reached when drag force equals weight
• Reaching terminal velocity


  1. Object accelerates

  2. Drag force increases

  3. Drag force equals weight

  4. No further acceleration
• Determining if ball reaches terminal velocity

  1. Measure time taken to fall set distance

  2. Calculate speed

  3. Repeat to find average speed

  4. If speed is constant, terminal velocity reached
• Circular motion


  Motion in a circular path at constant speed
• Speed


  How fast an object is traveling, a scalar quantity