Answer:
784.8 Newton
1051.2 Newton
Explanation:
[tex]W=mg\\\Rightarrow W=80\times 9.81\\\Rightarrow W=784.8\ N[/tex]
If the elevator is going down at a constant velocity then acceleration is zero and the apparent weight before braking is 784.8 N
t = Time taken
u = Initial velocity
v = Final velocity
s = Displacement
a = Acceleration
g = Acceleration due to gravity = 9.81 m/s²
[tex]v=u+at\\\Rightarrow a=\frac{v-u}{t}\\\Rightarrow a=\frac{0-10}{3}\\\Rightarrow a=-3.33\ m/s^2[/tex]
While the elevator is braking it has acceleration -3.33 m/s².
[tex]W=m(g-a)\\\Rightarrow W=80(9.81-(-3.33))\\\Rightarrow W=1051.2\ N[/tex]
The apparent weight of Zach would be 1051.2 Newton
