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Physics · Chapter 3: Speed–time graphs

Year 11 Science · About 14 minutes with activities · Turn your sound on

Chapter 3 · Speed–time graphs
How far apart?The tracker only knows speed
Constant speeda = 0
Speeding up
Slowing down
Steeperbigger a
Gentlersmaller a
Stoppedv = 0
d–t: stopped
v–t: steady speed
a = 12 ÷ 6 = 2 m s⁻²
Flat: a = 0
a = −12 ÷ 4 = −3 m s⁻²
d = v × theight × base = area
½ × 6 × 12 = 36 m
10 × 12 = 120 m
Total = 180 m36 + 120 + 24
Rectangle + triangle

Chapter 3 recap

  • Speed on the y-axis, time on the x-axis. Flat line = constant speed (a = 0); sloping line = speeding up or slowing down; on the time axis = stopped.
  • Gradient = acceleration = Δv ÷ Δt (rise ÷ run), in m s⁻². Steeper = greater acceleration; sloping down = negative (deceleration).
  • Area under the line = distance travelled. Rectangle = base × height; triangle = ½ × base × height; add the pieces.
  • Next: Chapter 4 · Forces and Newton's laws

How can you find distance from a graph of speed?

Chapter 3 · About 14 minutes · sound on

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