A car goes 20 meters in a second. What is its speed in Km/hr?
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → 72
1 km = 1000 m and 1 hour = 3600 s, so 1 m/s = 3600/1000 km/h = 18/5 km/h. To change m/s into km/h, multiply by 18/5.
The car covers 20 m every second: speed \(=20\,\mathrm{m/s}\)
In km/h: \(20\times\displaystyle\frac{18}{5}=72\,\mathrm{km/h}\)