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An elevator car whose floor to ceiling d...

An elevator car whose floor to ceiling distance is equal to `2.7 m` starts ascending with constant acceleration `1.2 m//s^(2)`, 2 sec after the start a bolt begins falling from the ceiling of the car. Answer the following question `(g=9.8 m//s^(2)`
The bolt's free falls time

A

0.3 s

B

0.5 s

C

0.7 s

D

0.9 s

Text Solution

Verified by Experts

The correct Answer is:
C
`y_(rel)=u_(rel)t+(1)/(2)a_(rel)t^(2)-2.7=0-(1)/(2)(9.8+1.2)t^(2)t=0.7sec`
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Knowledge Check

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