The speed of a car would be in kilometres/hour, the length would be in metres.
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NB: IN Britain, despite almost all other legal technical and commercial measurements being metric or SI, the Statute Mile and Yard remain the only legal road-measurement units.
A car is typically measured in meters, which is a unit of length. Four meters is a more common measurement for the size of a car. Four kilometers would be a much larger distance, typically used for measuring longer distances such as road trips or races.
4 meters
4 meters
Meters
The height of a typical car is usually around 1.5 to 2 meters, which translates to approximately 0.0015 to 0.002 kilometers. Therefore, cars are quite short in comparison to distances measured in kilometers.
milimeters
80,000 kilo meters
5 meters
speed.. distance..
4 metres
3 KILOMETERS
Anything that you might measure in yards, can easily be measured in meters. For example, the length of a car, the distance to cross a street, etc. You would NOT use meters to measure something rather small like the length of a pencil.