Grade 12th passMechanics

An elevator ascends from the ground with uniform speed. At time T1 a boy drops a marble through a hole in the floor. The marble hits the ground T2 seconds later. Find the height of the elevator at time T1.(T1=T2=4s)

Vaidehi

8 Years agoGrade 12th pass

2 Answers

downey zer

8 Years ago

Let the speed of the elevator be v

Then initially marble was also travelling at speed v.

when the marble fell from the hole the elevator was at height v*T1 as it was travelling at speed v for T1 time

now use

h=ut+0.5at^2

where h = – v*T1

a= – g, u=v

t=T2

putting T1=T2=4

u will get v=10

so height =v*T1=40

downey zer

8 Years ago

please approve the answer if it helped

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An elevator ascends from the ground with uniform speed. At time T1 a boy drops a marble through a hole in the floor. The marble hits the ground T2 seconds later. Find the height of the elevator at time T1.(T1=T2=4s)

Vaidehi

2 Answers

downey zer

downey zer

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