p9- motion

• What should higher tier students be able to use to determine the speed of an accelerating object?

  A tangent
• What does an upward sloping curve on a distance time graph indicate?

  The object is accelerating
• What are the steps to plot a distance time graph for a journey?

  1. Place a point at (0 m, 0 seconds).
  2. Plot the first distance and time point.
  3. Plot the stopping point at the same distance.
  4. Plot the second distance and time point.
  5. Connect the points with straight lines.
• How do you calculate speed from a distance time graph?

  • Identify distance traveled.
  • Identify time taken.
  • Use the formula: Speed = Distance / Time.
• What are the differences between speed and velocity?

  • Speed: scalar quantity, magnitude only.
  • Velocity: vector quantity, magnitude and direction.
• gradient equation

  distance traveled/time taken
• distance traveled ar any point

  1. place a dot on the point we want to find
  2. draw a tangent
  3. work out the gradient
• Why is velocity considered a vector quantity?

  It includes both magnitude and direction
• How is velocity defined?

  Speed in a given direction
• What happens to velocity when an object moves in a circle at constant speed?

  Velocity is constantly changing
• What is a key fact about objects moving in a circle?

  Constant speed means changing velocity
• What is the definition of velocity?

  Speed in a given direction
• What does acceleration tell us about an object's velocity?

  Change in velocity over a given time
• What does a negative acceleration indicate?

  The object is decelerating
• What does the gradient of a velocity-time graph represent?

  Acceleration of the object
• What does an upward sloping line on a velocity-time graph show?

  The object is accelerating
• What does a downward sloping line on a velocity-time graph indicate?

  The object is decelerating
• What does the total area under a velocity-time graph represent?

  Distance traveled in a specific direction
• How do you estimate the total area under a graph when acceleration and deceleration are not constant?

  Count squares and estimate partial squares
• What force acts on a skydiver as they fall?

  Force of gravity
• What is air resistance?

  Upward force of friction with air particles
• What happens when air resistance balances the force of gravity?

  The object moves at terminal velocity
• What type of fluid is mentioned in relation to falling objects?

  Air and liquids
• What are the steps to calculate acceleration from given velocities and distance?

  1. Identify initial and final velocities
  2. Determine distance traveled
  3. Use the rearranged acceleration equation
  4. Solve for acceleration
• What happens to an object falling through a fluid?

  • Initially accelerates due to gravity
  • Experiences air resistance upward
  • Reaches terminal velocity when forces balance
  • Terminal velocity varies by object shape
• How does speed affect braking distance?

  Higher speed increases braking distance significantly
• What happens to kinetic energy when velocity is doubled?

  Kinetic energy quadruples
• What causes the temperature of the brakes to increase during braking?

  Conversion of kinetic energy to thermal energy
• What is required to stop a car traveling at high speeds?

  A large braking force is needed
• What is the final speed of the car after deceleration?

  Zero meters per second
• What are the energy changes during vehicle braking?

  • Kinetic energy converts to thermal energy
  • Brakes heat up due to energy conversion
  • Loss of kinetic energy slows the vehicle
• What factors affect the braking force needed to stop a vehicle?

  • Speed of the vehicle
  • Mass of the vehicle
  • Desired stopping distance
• How do you estimate forces involved in vehicle deceleration?

  1. Identify mass of the vehicle
  2. Determine initial and final velocities
  3. Calculate acceleration
  4. Use force = mass × acceleration