Question

Convert a speed of 315km/h to speed in m/s.

Answer 1

To convert km/h to m/s we multiply the given number by $\dfrac{5}{18}$.

Complete step-by-step answer:
Given speed is 315km/h.
To convert km/h in m/s we can multiply the given number by $\dfrac{5}{18}$.
We can write it as
$\Rightarrow 315km/h=315\times \dfrac{5}{18}m/s$
$\Rightarrow 315km/h=\dfrac{1575}{18}m/s$
$\Rightarrow 315km/h=87.5m/s$
Hence value of 315 km/h in m/s is 87.5

Note: In general 1km = 1000m
1 hr = 3600 sec
So we can convert 1km/h to m/s as given below:
$1\,km/h=\,\dfrac{1000}{3600}m/s$
Now we can divide numerator and denominator by 200
$1\,km/h=\,\dfrac{\dfrac{1000}{200}}{\dfrac{3600}{200}}m/s$
$1\,km/h=\,\dfrac{5}{18}m/s$
That’s why we say to convert km/h to m/s we multiply by $\dfrac{5}{18}$.