Zach, whose mass is 66 kg, is in anelevator descending at 8 m/s. The elevatortak

Question

Zach, whose mass is 66 kg, is in anelevator descending at 8 m/s. The elevatortakes 2.1 s to brake to a stop at thefirst floor.

(a) What is Zach's apparent weight before theelevator starts braking?
1_____ N
(b) What is Zach's apparent weight while the elevator isbraking?
2_____ N

Please indicate which answer is a and which is b.
(a) What is Zach's apparent weight before theelevator starts braking?
1_____ N
(b) What is Zach's apparent weight while the elevator isbraking?
2_____ N

Please indicate which answer is a and which is b.

Explanation / Answer

mass m = 66 kg (a). Zach's apparent weight before the elevator starts braking= m g                                                                                            = 66 * 9.8 = 646.8 N (b). Zach's apparent weight while the elevator isbraking = m ( g + a ) where a = acceleration = ( v - u ) / t            u= initial velocity = 8 m / s            v= final velocity = 0            t= time = 2.1 s So, a = -8 / 2.1= - 3.809 m / s ^ 2 Thereforce apperent weight = 66 ( 9.8 -3.809 ) =395.37 N

Related Questions

Navigate

• Browse (All)
• Browse Z
• Subjects

---