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3 years ago

Un autocar que circula a 81 km/h frena uniformemente con una aceleración de -4,5 m/s2.

Physics

1 answer:

horsena [70]3 years ago

8 0

Answer:

a) $\Delta x=56.25 m$

b) imagen adjunta

Explanation:

a) Primero debemos hacer la conversión de 81 km/h a m/s, esto es 22.5 m/s.

Ahora, usando la ecuacion cinemática, en un movimiento acelerado tenemos:

$v_{f}^{2}=v_{0}^{2}+2a \Delta x$

Queremos encontrar la posición hasta detenerse, osea vf = 0.

$\Delta x=\frac{-v_{0}^{2}}{2a}$

$\Delta x=\frac{-22.5^{2}}{-2*4.5}$

$\Delta x=56.25 m$

b) Para este caso el gráfico se encuentra adjunto.

Espero que te sirva de ayuda!

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