Question

un automovil marcha a la velocidad de 72 km/h si al frenar el vehiculo se detiene al cabo de 12 segundos... determina la aceleración retardatriz

Answer 1

$\[\begin{gathered} {v_f} = {v_0} - at \hfill \\ {v_f} = 0 \hfill \\ 0 = {v_0} - at \hfill \\ \end{gathered} \]$

$\[a = \frac{{{v_0}}}{t}\]$

$\[\begin{gathered} a = \frac{{72\frac{{km}}{h}}}{{12s}} \hfill \\ a = \frac{{72\frac{{km}}{h}\frac{{1000m}}{{km}}\frac{h}{{3600s}}}}{{12s}} \hfill \\ \end{gathered} \]$

Finalmente:

$\[a = 1.67\frac{m}{{{s^2}}}\]$