The brakes on an elevator of weight 50,000 N act upward with a force of 100,000 N the acceleration of elevator while braking would be____A) 9.8 m/s^2 downB) 1.9 m/s^2 upC) 3.17 m/s^2 upD) 9.8 m/s^2 up

Respuesta :

Using newton's second law:

[tex]\begin{gathered} \Sigma Fy=ma \\ 50000-100000=\frac{50000}{9.8}a \\ solve_{\text{ }}for_{\text{ }}a: \\ a=9.8(\frac{50000-100000}{5000}) \\ a=-9.8m/s^2 \end{gathered}[/tex]

Answer:

D) 9.8 m/s^2 up