Understand the relationship between speed, distance, and time
Use the speed formula triangle
Calculate speed, distance, or time when given the other two
Work with different units (mph, km/h, m/s)
🌟 Why It Matters
Speed calculations help us plan journeys, understand sports performance, compare vehicles, and solve everyday problems about how long things take to travel from one place to another.
📐 The Speed Triangle
D
S
T
Cover what you want to find - the remaining parts show the calculation!
S = D ÷ T
Speed = Distance ÷ Time
How fast something goes
D = S × T
Distance = Speed × Time
How far something travels
T = D ÷ S
Time = Distance ÷ Speed
How long a journey takes
📏 Understanding Units
Distance
metres (m)
kilometres (km)
miles
centimetres (cm)
Time
seconds (s)
minutes (min)
hours (h)
days
Speed
metres per second (m/s)
kilometres per hour (km/h)
miles per hour (mph)
feet per second (ft/s)
🧮 Speed-Distance-Time Calculator
Calculate Speed
Speed:50 km/h
Formula: Speed = Distance ÷ Time
S = 100 km ÷ 2 h = 50 km/h
Calculate Distance
Distance:180 km
Formula: Distance = Speed × Time
D = 60 km/h × 3 h = 180 km
Calculate Time
Time:3 hours
Formula: Time = Distance ÷ Speed
T = 120 km ÷ 40 km/h = 3 h
🌍 Real-World Examples
🚗 Car Journey
A car travels 150 miles in 3 hours. What is its average speed?
Speed = Distance ÷ Time
Speed = 150 miles ÷ 3 hours = 50 mph
Average speed: 50 mph
🏃♂️ Running
A runner maintains 12 km/h for 45 minutes. How far do they run?
Distance = Speed × Time
Distance = 12 km/h × 0.75 h = 9 km
Distance: 9 kilometres
✈️ Flight Time
An airplane flies 600 km at 400 km/h. How long is the flight?
Time = Distance ÷ Speed
Time = 600 km ÷ 400 km/h = 1.5 hours
Flight time: 1.5 hours (1 hour 30 minutes)
🔄 Unit Conversions
Speed Conversions
1 m/s = 3.6 km/h
1 km/h = 0.278 m/s
1 mph = 1.609 km/h
1 km/h = 0.621 mph
Distance Conversions
1 km = 1000 m
1 mile = 1.609 km
1 km = 0.621 miles
1 m = 100 cm
Time Conversions
1 hour = 60 minutes
1 minute = 60 seconds
1 hour = 3600 seconds
0.5 hours = 30 minutes
💪 Practice Exercises
1. A car travels 120 km in 2 hours. What is its speed?
Use Speed = Distance ÷ Time. So 120 km ÷ 2 hours = ?
2. If a train travels at 80 km/h for 3 hours, how far does it go?
Use Distance = Speed × Time. So 80 km/h × 3 hours = ?
3. How long does it take to travel 150 miles at 50 mph?
Use Time = Distance ÷ Speed. So 150 miles ÷ 50 mph = ?
4. Which formula is used to find speed?
Remember the speed triangle: cover S to see D ÷ T
5. Calculate: A cyclist travels 45 km in 1.5 hours. What is their speed in km/h?