Speed, distance and time: Kathmandu to Pokhara
Send a bus and a later motorbike along the 200 km highway, read a distance–time graph and find where the bike catches the bus.
Core concept
In short: Drive along a highway and see how distance, speed and time fit together.
distance = speed × time; on a distance–time graph a steeper line means a higher speed
Topic: Speed, distance and time
The road from Kathmandu to Pokhara is about 200 km, passing Mugling at about 110 km. A bus travels at a steady speed: How far something travels in a certain time, like kilometres per hour. All key words, for example 40 km/h: it covers 40 km every hour, so after t hours it has gone 40 × t km, and the whole trip takes 200 ÷ 40 = 5 hours. A motorbike leaves an hour later but goes faster. On a distance–time graph each trip is a line; the steeper the line, the faster the vehicle. Where the two lines cross, the bike has caught the bus.
What you will learn
- Use distance = speed × time, and find time = distance ÷ speed.
- Read and compare lines on a distance–time graph.
- Find when and where a faster vehicle that starts later catches up.
Before you start
- Multiplying and dividing whole numbers and halves.
Materials
- A map of the Prithvi Highway
Equipment
- Graph paper
Procedure
- Tap − or + to change the bus speed, the bike speed and how late the bike leaves.
- Drag the dashed clock line along the graph and watch both vehicles on the road.
- Record the moment the bike catches the bus, and a time when the bike is ahead.
- Record the bus reaching Pokhara at 40 km/h, and how long it takes at 50 km/h.
How this simulation is simplified
- Both travel at steady speeds without stopping; the route is 200 km.