Question

A rocket travels at a speed of 15,000 m/s. Express this speed in km/h

Answer 1

km/hr = 1 km/1 hr = 1 × 1000 m/60 × 60 sec = 1000/3600 m/sec = 5/18 m/sec                                 

So, we say that to convert km/hr into m/sec, we multiply by 5/18.