Calculation 36671

A boy leaves school at a speed of 1 m/s. At the moment, when he is 100m away from the school, a classmate on a bicycle comes behind him at a speed of 5m/s. How long and how far does the boy run from school? Solve by calculation and graphically.

Correct answer:

t =  25 s
s₂ =  125 m

Step-by-step explanation:

$$\begin{gathered} v_1=1\text{m/s} \\ {v}_2=5\text{m/s} \\ s=100\text{m} \\ {s}_1=s_2 \\ s+v_1\cdot t=v_2\cdot t \\ t=s/(v_2-v_1)=100/(5-1)=25\text{s} \end{gathered}$$

$s_2=v_2\cdot t=5\cdot 25=125\text{m}$

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