An elevator ascends from the ground with uniform speed. a time tį later, a boy drops a marble through a hole in the floor. a time t2 after that (i. e. ti +t2 after start) the marble hits the ground. find an expression for the height of the elevator at time ti. (local gravity is g.) what checks can you make?

The height of the elevator at is

Solution:

As per the question:

Let us assume:

The velocity with which the elevator ascends be u'

The height attained by the elevator at time, be h

Thus

    (1)_

Now, with the help of eqn (2) of motion, we can write:

Using eqn (1):

there are no contact forces mentioned on the list of choices that you've provided.