Please solve question 147?

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1 Answer
Apr 7, 2018

The answer is #"option (2)"#

Explanation:

The net force acting upwards on the ball is

#F=Vg(d-D)#

The work done to take the wooden ball to depth #h# below the surface of water is

#W=Fh=Vg(d-D)h#

Let the height above the surface of water be #=H#

Then,

The potential energy of the ball is #PE=mgH=VDgH#

As

#PE= W#

#VDgH=Vg(d-D)h#

#H=(d-D)/(D)h#

#H=(d/D-1)h#

The answer is #"option (2)"#