Question

An elevator car whose floor to ceiling distance is equal to 2.7m starts ascending with constant acceleration 1.2 m//s^2. 2 s after the start, a bolt begins falling from the ceiling of the car. Find
(a)the time after which bolt hits the floor of the elevator.
(b)the net displacement and distance travelled by the bolt, with respect to earth. (Take g=9.8 m//s^2)

Answer 1

Answer:

Let H be the height of the building and t be the time to fall through this height H.

Then H = ½ g t^2 = 5 t^2. ----------------- (1)

In (t-1) second the distance traveled is 1 - 0.36 H = 0.64 H.

0.64 H = 5 (t-1)^2.---------------------------(2)

(2) / (1) gives 0.64 = (t-1)^2/ t^2

Or 0.8 = (t-1) / t

Solving we get t= 5 second.

Using (1) we get H = 125 m.

Answer 2

height = 125 m

is ur answer.....