Why 36 km/h equals 10 m/s: convert both distance and time
A speed unit contains a distance unit and a time unit. Converting kilometres to metres without converting hours to seconds creates a large error.
Speed, distance and time calculator →Follow the units step by step
36 km/h equals 36000 metres divided by 3600 seconds, which is 10 m/s. Therefore divide km/h by 3.6 to obtain m/s, and multiply m/s by 3.6 for the reverse conversion. As a second check, 72 km/h equals 20 m/s. The factor comes from both unit changes, not from an arbitrary shortcut.
Verify the same motion in the calculator
A distance of 100 m covered in ten seconds gives 10 m/s. Selecting km/h for the output should display 36. Changing the output unit does not change the motion being described. Entering the number 100 while selecting kilometres instead of metres, however, changes the input scenario completely.
Keep average and instantaneous speed separate
Distance divided by total time gives average speed. It does not prove that the object maintained that speed every second. Acceleration, braking distance and changing velocity require additional models and information. The calculator does not determine safe following distance or compliance with a local speed limit. The unit converter can check representations, and the pace tool describes time per distance for running, but neither supplies the missing motion history.
Try the calculators
- Speed, distance and time calculator
Solve for speed, distance or time from the other two, with metric and imperial units.
- Unit converter
Convert length, mass, area, volume, speed and data size.
- Pace calculator
Turn distance and time into pace and speed.