Speed, Distance and Acceleration

• What is acceleration defined as?


  The rate of change in velocity
• What are the units of acceleration?


  • Meters per second squared (m/s²)
• How can acceleration be simply described?


  How quickly something speeds up or slows down
• How is change in velocity represented mathematically?


  Δv = v - u
• What does the delta sign (Δ) represent in physics?


  Change
• In the equation Δv = v - u, what do v and u represent?


  v is the final velocity and u is the initial velocity
• If a car accelerates from 15 m/s to 35 m/s in 5 seconds, what is the change in velocity?


  20 m/s
• How do you calculate acceleration if you know the change in velocity and time?


  Acceleration = Δv / time
• Why can acceleration be negative?


  It implies that the object is slowing down or decelerating
• What does average acceleration refer to?


  The average change in velocity over a specific time period
• What is uniform or constant acceleration?


  Acceleration that remains the same throughout the time period
• When should you use the equation that includes distance instead of time for acceleration?


  When the unit of distance is given
• What is the initial velocity (u) of an object that starts from rest?


  0 m/s
• What do distance-time graphs allow us to visualize?


  They allow us to visualize how far something has traveled in a certain period of time.
• What does the gradient of the line on a distance-time graph represent?


  The gradient represents the speed of the object at that time.
• What is the formula for speed in terms of distance and time?


  Speed = change in distance / change in time
• What does a flat line on a distance-time graph indicate?


  It indicates that the object is stationary.
• What does a steeper line on a distance-time graph signify?


  It signifies that the speed is increasing.
• What does a decreasing gradient on a distance-time graph represent?


  It represents deceleration.
• How can you find the speed at a particular point on a curve in a distance-time graph?


  You need to draw a tangent to the curve at that point.
• What is a tangent in the context of a distance-time graph?


  A tangent is a straight line that has the same gradient as the curve at the point where they touch.
• How do you calculate the gradient of the tangent to find speed?


  By dividing the change in distance by the change in time.
• What do straight lines, flat lines, and curved lines represent on a distance-time graph?


  • Straight lines represent constant speeds.
  • Flat lines mean stationary.
  • Curved lines represent changing speeds.
• What should you do if the point lies on a straight line on a distance-time graph?


  You calculate the gradient of the line by dividing the change in distance by the change in time.
• What should you do if the point lies on a curve on a distance-time graph?


  You need to draw a tangent to the curve at that point and then calculate the gradient of that tangent.
• What are the key points to remember about distance-time graphs?


  • Straight lines = constant speed
  • Flat lines = stationary
  • Curved lines = changing speeds
  • Calculate speed using gradient
• What do distance-time graphs show?


  How the distance of an object varies over time
• What do velocity-time graphs show?


  How an object's velocity changes over time
• What is plotted on the y-axis of a velocity-time graph?


  Velocity
• Why is it easy to confuse distance-time graphs with velocity-time graphs?


  Because both graphs look similar
• What is plotted on the x-axis of a velocity-time graph?


  Time
• How do you find the gradient of the curve on a velocity-time graph?


  By calculating the change in velocity over the change in time
• What does the gradient of a velocity-time graph represent?


  The acceleration of the object
• What does a constant positive gradient on a velocity-time graph indicate?


  Constant acceleration
• What does a constant negative gradient on a velocity-time graph indicate?


  Constant deceleration
• If the change in velocity is 3 m/s and the change in time is 2 s, what is the acceleration?


  $1.5 \text{ m/s}^2$
• What does a flat section of the curve on a velocity-time graph indicate?


  That the velocity is constant
• How do you find the velocity during flat sections of a velocity-time graph?


  By looking at the y-axis
• What is the velocity during the second stage if it is 3 m/s?


  3 m/s
• What is the velocity during the fourth stage if it is 5 m/s?


  5 m/s