# My motorcycle travels 220 km in 2.25 hours. How would I correctly express its velocity in the appropriate SI units, ms^-1?

Aug 28, 2016

We need to convert km to m and hours to s.

$v = \frac{d}{t} = \frac{220 , 000}{8100} = 27.2$ $m {s}^{-} 1$.

#### Explanation:

There are 1000 m in 1 km, so multiply by 1000: $220 \times 1000 = 220 , 000$ $m$.

There are 60 minutes in 1 hr and 60 seconds in 1 min, so multiply by $60 \times 60 = 3600$: $2.25 \times 3600 = 8100$ $s$.

Mar 28, 2018

$24.44 \setminus {\text{m/s"=24.44 \ "ms}}^{-} 1$.

#### Explanation:

Well, your velocity in $\text{km/h}$ is:

$220 \setminus \text{km/2.25 h}$

$= 88 \setminus \text{km/h}$

We know that $1 \setminus \text{m/s"=3.6 \ "km/h}$, and so your speed in $\text{m/s}$ is:

$\frac{88}{3.6} = 24. \overline{4}$

$\approx 24.44 \setminus \text{m/s}$