Question

How fast is 54 km per second in mph?

Answer 1

54km/s

change km to m

1km=1000m

54 km=54000m....(1)

now change s to hr

1h=60*60s

=3600hr....(2)

So 54 km/1hr=54000 m /3600 hr[By dividing the 2 equations]

=15m/h

Hope it helps you mate.