To the city

A bus leaves for a city 54 km away at an average speed of 15 m/s. 12 minutes after the bus leaves, a motorcycle leaves from the same place to follow it. Calculate the average speed of the motorcycle when it arrives at the destination at the same time as the bus.

Final Answer:

v₂ =  18.75 m/s

Step-by-step explanation:

$$\begin{gathered} s=54\text{km}\to \text{m}=54\cdot 1000\text{m}=54000\text{m} \\ {v}_1=15\text{m/s} \\ {t}_1=12\text{min}\to \text{s}=12\cdot 60\text{s}=720\text{s} \\ t=s/v_1=54000/15=3600\text{s} \\ {v}_2=\frac{s}{t-t_1}=\frac{54000}{3600-720}=18.75\text{m/s} \end{gathered}$$

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