BÊTACette plateforme est en développement actif ; des bugs, des fonctionnalités manquantes et un risque de perte de données sont possibles. Merci pour ton soutien !

Speed

Apprends en jouant

Réponds à ces questions pour gagner de l'énergie, puis pêche et explore. Sans compte.

Pour les profs : diapos de leçon, notes de révision prêts à l'emploi pour Speed (KS3 Science, Physics) — utilise-les en cours, ou lance le thème en activité de classe interactive que tes élèves jouent en direct.

Notes de leçon

What is Speed?

  • Speed is a measure of the distance an object moves in a certain time.
  • Common units include miles per hour (mph) and kilometres per hour (km/h).
  • In physics, speed is usually measured in metres per second (m/s).
  • Constant speed means the same distance is covered each second (e.g., 30 m/s = 30 m every second).

Calculating Speed

  • The equation for speed is: Speed = Distance ÷ Time.
  • Example: A car travels 400 m in 20 s → Speed = 400 ÷ 20 = 20 m/s.
  • Always include the correct units (m/s) in your answer.

Calculating Distance

  • Rearrange the speed equation: Distance = Speed × Time.
  • Example: An athlete runs at 8 m/s for 50 s → Distance = 8 × 50 = 400 m.

Calculating Time

  • Rearrange the speed equation: Time = Distance ÷ Speed.
  • Use this when you know distance and speed and need to find time.

Relative Speed

  • The speed of one object relative to another can be found by adding speeds.
  • Example: Car at 30 m/s, train 20 m/s faster → train speed = 30 + 20 = 50 m/s.

Units and Conversions

  • Speed units: m/s (metres per second), km/h (kilometres per hour), mph (miles per hour).
  • In calculations, ensure distance and time are in compatible units (e.g., metres and seconds).

Worked Examples

  • Cyclist: 120 m in 20 s → Speed = 120 ÷ 20 = 6 m/s.
  • Runner: 1500 m in 500 s → Speed = 1500 ÷ 500 = 3 m/s.
  • Dog walker: 1200 m in 1000 s → Speed = 1200 ÷ 1000 = 1.2 m/s.

Key Points

  • Speed = Distance ÷ Time is the core formula.
  • You can rearrange it to find distance or time.
  • Constant speed means the object covers equal distances in equal time intervals.

Diapos

Sign up free to view the lesson slides

Step through every slide for this topic — plus flashcards and revision notes — with a free account.

Questions d'entraînement

Aperçu gratuit — 8 sur 71 questions. Inscris-toi pour toutes les voir.
  1. 1.What is speed a measure of?

    Easy
    • AThe distance an object has moved in a certain time
    • BThe time an object takes to move a certain distance
    • CThe force acting on an object
    • DThe mass of an object
  2. 2.Which of the following is the correct equation for speed?

    Easy
    • ASpeed = Distance × Time
    • BSpeed = Distance ÷ Time
    • CSpeed = Time ÷ Distance
    • DSpeed = Distance + Time
  3. 3.An object is travelling at a constant speed of 20 m/s. How far does it travel every second?

    Easy
    • A20 m
    • B10 m
    • C40 m
    • D5 m
  4. 4.A car is travelling at 20 m/s and a train is travelling 10 m/s faster than the car. What is the speed of the train?

    Easy
    • A10 m/s
    • B20 m/s
    • C30 m/s
    • D200 m/s
  5. 5.A cyclist travels a distance of 120 m in 20 seconds. What is the cyclist's speed?

    Medium
    • A6 m/s
    • B2400 m/s
    • C0.17 m/s
    • D100 m/s
  6. 6.A runner travels 1500 m in 500 s. What is the runner's speed?

    Medium
    • A3 m/s
    • B750000 m/s
    • C0.33 m/s
    • D1000 m/s
  7. 7.A sound wave travels 686 m in 2 seconds. What is the speed of sound?

    Medium
    • A343 m/s
    • B1372 m/s
    • C344 m/s
    • D684 m/s
  8. 8.Light travels 4,500,000,000 m in 15 seconds. What is the speed of light?

    Medium
    • A300,000,000 m/s
    • B300,000 m/s
    • C67,500,000,000 m/s
    • D4,500,000,015 m/s

Unlock all 71 questions, flashcards & more

Crée un compte gratuit pour voir toutes les questions, les diapos, les cartes mémo et les notes de révision de ce thème.

Annales

Les annales d'entraînement pour ce thème arrivent bientôt.
Bientôt disponible