Question

An elevator is accelerating upward at a rate of `6ft(sec^(2)` when a bolt from its celling falls to the floor of the lift (Distance=9.5feet). The time taken (in seconds) by the falling bolt to hit the floor is (take `g=32ft//sec^(2)`)
A. `sqrt(2)`
B. `(1)/sqrt(2)`
C. `2sqrt(2)`
D. `(1)/(2sqrt(2))`

Answer 1

Correct Answer - B
Effective acceleration in ascending lift =(g_f)
`therefores=ut+(1)/(2)at^(2)`
`9.5=0+(1)/(2)(g+f)t^(2)`
or `9.5=(1)/(2)(32+6)t^(2)`
or `t^(2)=(9.5xx2)/(38)=(1)/(2)`
or `t=(1)/sqrt(2)` sec