Kilometers - subway

A subway train covers a distance of 1.4 km between two adjacent stations in 1 minute 40 seconds. What is her average speed? Give the result in kilometers per hour and meters per second.

Correct answer:

v₁ =  50.4 km/h
v₂ =  14 m/s

Step-by-step explanation:

$$\begin{gathered} s=1.4\text{km} \\ t=0:1:40=0hr1min40sec=0+\frac{1}{60}+\frac{40}{3600}=0.0169hr\doteq 0.0278 \\ {v}_1=s/t=1.4/0.0278=50.4\text{km/h} \end{gathered}$$

$v_2=v_1\to \text{m/s}=v_1:3.6\text{m/s}=50.4:3.6\text{m/s}=14\text{m/s}=14\text{m/s}$

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