OpenOlympiad
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Speed, uniform vs non-uniform motion

Speed tells how fast something moves. It's just how far something travels in a given time.

Speed = Distance ÷ Time

Common units: m/s (metres per second), km/h (kilometres per hour).

Conversion: 1 m/s = 3.6 km/h. (Or: divide km/h by 3.6 to get m/s.)

Two kinds of motion:

  • Uniform motion: same speed throughout. Equal distance in equal time.
  • Non-uniform motion: speed changes. Most real-world motion is non-uniform.

Average speed = Total distance ÷ Total time (even if speed varied on the way).

Example
A car travels 180 km in 3 hours. Average speed = 180/3 = 60 km/h = 60/3.6 ≈ 16.7 m/s.
A runner finishes 100 m in 10 s — avg speed 10 m/s = 36 km/h.
💡 Tip:Even if a car's speedometer reads 60 km/h constantly, it's in uniform motion. In a city, starting/stopping means non-uniform motion.
Prefer a video? Open YouTube search for “speed distance time class 6

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5 questions to check what you just read.

0 / 5
  1. Q1.Speed = ?
  2. Q2.Car travels 180 km in 3 h. Avg speed:
  3. Q3.72 km/h in m/s:
  4. Q4.Walking speed 5 km/h means in 2 h:
  5. Q5.Uniform motion means: