A sprinter runs 100 m in 10 s, how fast in km/h?

Question

Solve in your head. A sprinter covers 100 metres in 10 seconds. What is that speed in kilometres per hour? Aim: under 10 seconds.

Accepted Answer

First get metres per second directly from the definition of speed: \frac{100 	ext{ m}}{10 	ext{ s}} = 10 	ext{ m/s}. Then convert m/s to km/h by multiplying by 3.6: 10 	imes 3.6 = 36 	ext{ km/h}. Takeaway. Two-step speed questions collapse to distance-over-time first, then the 3.6 factor. The clean anchor to remember: 10 m/s = 36 km/h, the exact pace of a 10-second 100-metre dash.

A sprinter runs 100 m in 10 s, how fast in km/h?

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