Answer: [tex]3.816\ m/s[/tex]
Explanation:
Given
Mass of Henry is 95 kg
Normal weight of Henry is [tex]mg=95\times 9.8=931\ N[/tex]
The scale reads the weight as 830 N for first 3.6 s i.e. less than the normal weight i.e. Elevator is moving downwards
Apparent weight is given by
[tex]\Rightarrow 830=m(g-a)\quad [a=\text{acceleration of elevator}]\\\Rightarrow 830=95(9.8-a)\\\Rightarrow 8.736=9.8-a\\\Rightarrow a=1.06\ m/s^2[/tex]
After 3.6 s weight becomes 930 N which is approximately equal to normal weight. It implies elevator starts moving with constant velocity i.e. no acceleration.
If elevator starts from rest, it velocity after 3.6 s is
[tex]v=u+at\\\Rightarrow v=0+1.06(3.6)\\\Rightarrow v=3.816\ m/s[/tex]
This velocity will remain continues as after 3.6 s, elevator starts moving with constant velocity.
