📏 What is Distance?
Distance is how far an object travels. It's the total length of the path something moves along. When you walk from your bedroom to the kitchen, the distance is the length of the route your feet take to get there!
Measuring Distance
Distance is measured in units of length. The unit we choose depends on how far the object travels:
📝 Units of Distance:
- Millimeters (mm) — tiny things, like the width of a fingernail
- Centimeters (cm) — small things, like the length of a pencil
- Meters (m) — everyday things, like the height of a door
- Kilometers (km) — long trips, like the distance to school
Finding Distance from Speed and Time
If you know how fast something is going and for how long, you can figure out the distance it traveled:
🧮 Distance Formula:
\( \text{Distance} = \text{Speed} \times \text{Time} \)
\( d = s \times t \)
📝 Let's Try It:
If a car travels at 20 m/s for 30 seconds, the distance is:
\( 20\ \text{m/s} \times 30\ \text{s} = 600\ \text{meters} \)
The car traveled 600 meters — that's about 6 football fields!
Distance vs. Displacement
💡 The Round Trip:
Imagine you walk 10 meters to a tree and then walk 10 meters back. The total distance you walked is 20 meters. But your displacement — how far you ended up from the start — is 0 meters, because you're right back where you began!
- Distance: the whole path you traveled (always counts up)
- Displacement: how far you are from the starting point, and in what direction
📚 Quick Summary
📏 Distance
The total length of the path an object travels
🧮 Formula
Distance = Speed × Time \( (d = s \times t) \)
📐 Units
mm, cm, meters, and kilometers
🧭 Displacement
How far you end up from the start
➡️ Keep Exploring
🏃 Speed
Learn about speed — how fast the distance gets covered.
⏱️ Time
Learn about time — how long the journey takes.
🚀 Acceleration
Learn about acceleration — changing speed along the way.