Motorcyclist 82445

Motorcyclist Arnošt begins to move on his motorcycle in a uniformly accelerated motion with an acceleration of 1.6 m/s². At what time will it reach a speed of 50 km/h? What distance will it travel at this time?

Correct answer:

t =  8.6806 s
s =  60.2816 m

Step-by-step explanation:

$$\begin{gathered} a=1.6{\text{m/s}}^2 \\ v=50\text{km/h}\to \text{m/s}=50:3.6\text{m/s}=13.88889\text{m/s} \\ v=a\cdot t \\ t=v/a=13.8889/1.6=8.6806\text{s} \end{gathered}$$

$s=\frac{1}{2}\cdot a\cdot t^2=\frac{1}{2}\cdot 1.6\cdot 8.6806^2=60.2816\text{m}$

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