s

1. 2. Converting to SI units, we use Eq. 2-3 with d for distance.
savg =
d
t
(110.6 km/h)
1000 m/km
3600 s/h
=
200.0 m
t
which yields t = 6.510 s. We converted the speed km/h → m/s by converting each unit (km → m, h → s)
individually. But we mention that the “one-step” conversion can be found in Appendix D (1 km/h =
0.2778 m/s).