The MRT train

The MRT running from Taft to North Avenue has a starting velocity of 60km/hr. After a malfunction, the brakes failed, making the train run at a velocity of 80km/hr. What is the acceleration rate if the time for velocity change is 5 seconds?

Correct answer:

a =  1.1111 m/s²

Step-by-step explanation:

$$\begin{gathered} v_1=60\text{km/h}\to \text{m/s}=60:3.6\text{m/s}=16.66667\text{m/s} \\ {v}_2=80\text{km/h}\to \text{m/s}=80:3.6\text{m/s}=22.22222\text{m/s} \\ t=5\text{s} \\ a=\frac{v_2-v_1}{t}=\frac{\frac{200}{9}-\frac{50}{3}}{5}=\frac{10}{9}{\text{m/s}}^2=1.1111{\text{m/s}}^2 \end{gathered}$$

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