acceleration

• What is the definition of velocity?

  Speed in a given direction
• Why is velocity considered a vector quantity?

  It has both magnitude and direction
• What does acceleration tell us about an object's velocity?

  Change in velocity over a given time
• How is acceleration calculated?

  Change in velocity divided by time
• What is the unit of acceleration?

  m/s²
• What is the change in velocity if a car accelerates from 15 m/s to 35 m/s?

  20 m/s
• If a car accelerates from 15 m/s to 35 m/s in 20 seconds, what is its acceleration?

  1 m/s²
• What does an acceleration of 1 m/s² mean for the car?

  Velocity increases by 1 m/s every second
• If a cyclist's velocity reduces from 6 m/s to 0 in 12 seconds, what is her acceleration?

  -0.5 m/s²
• What does a negative acceleration indicate?

  Deceleration
• What does the gradient of a velocity-time graph represent?

  Acceleration of the object
• What does a horizontal line on a velocity-time graph indicate?

  Constant velocity
• What does an upward sloping line on a velocity-time graph show?

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

  Object is decelerating
• How do you calculate acceleration from a velocity-time graph?

  Subtract initial velocity from final velocity
• If the final velocity is 15 m/s and the initial velocity is 0 over 100 seconds, what is the acceleration?

  0.15 m/s²
• If the final velocity is 0 m/s and the initial velocity is 50 m/s over 300 seconds, what is the acceleration?

  -0.5 m/s²
• What does the total area under a velocity-time graph represent?

  Distance traveled in a specific direction
• How do you calculate the total area under a velocity-time graph with constant acceleration or deceleration?

  • Divide the graph into shapes
  • Calculate the area of each shape
  • Sum the areas to find total distance
• If a triangle has an area of 750, a rectangle has an area of 1500, and another triangle has an area of 2250, what is the total distance traveled?

  4500 m
• How do you estimate the total area under a velocity-time graph with non-constant acceleration or deceleration?

  • Count complete squares
  • Estimate parts of squares
  • Multiply total squares by area of each square
• If there are 20 squares under a graph and each square has an area of 250, what is the total distance or displacement?

  5000 m
• What should you be able to calculate by the end of the video?

  Velocity of an object accelerating
• How is acceleration calculated?

  Change in velocity divided by time
• What equation is used for constant acceleration?

  Final velocity squared minus initial velocity squared
• What is the acceleration of an object falling towards Earth?

  Approximately 9.8 meters per second squared
• 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 stops accelerating and moves at constant velocity
• What is the term for the constant velocity reached by falling objects?

  Terminal velocity
• What does terminal velocity depend on?

  Shape of the object and friction force
• What is the fluid through which a skydiver falls?

  Air
• What happens to terminal velocity in liquids compared to air?

  Similar effects occur in both fluids
• What are the key points about calculating distance using the acceleration equation?

  • Rearrange the equation as needed
  • Substitute known values accurately
  • Understand the relationship between velocity, acceleration, and distance
• 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
• What are the effects of air resistance on falling objects?

  • Acts upward against gravity
  • Balances gravitational force at terminal velocity
  • Influences the speed and shape of falling objects
• What are the implications of terminal velocity for different objects?

  • Varies based on shape and mass
  • Affects how quickly objects fall
  • Important for understanding motion through fluids