# Water displaced against surface area

If 2 differently shaped objects are submerged in water, say one is rectangular and other spherical, and both displaces the same volume of water, would the surface area of both objects be the same?

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Borek
Mentor
I don't see how water is relevant here.

Basically you are asking if two objects of the same volume have the same surface.

Let's see - calculate volume and surface of two cuboids. One 3x3x3 and the other 1x1x27.

Thanks, what is given actually is the water displacement of a ship and I must find out the surface area of the hull below waterline. But hull shapes design vary according to vessel application. So what you're saying is surface area can be computed given the water displacement of the hull regardless of its shape.

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Borek
Mentor
What I am saying is try to calculate volume and surface of two given cuboids. Do it.

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methods

cuboids 3x3x3 and 1x1x27 have the same volume but different surface areas. check your math

if 2 differently shaped objects are submerged in water, say one is rectangular and other spherical, and both displaces the same volume of water, would the surface area of both objects be the same?
no.........

Borek
Mentor
cuboids 3x3x3 and 1x1x27 have the same volume but different surface areas. check your math
I have never said they have identical surface & volume. However, now you should be able to answer your question from the very first post:

If 2 differently shaped objects (...) displace the same volume of water, would the surface area of both objects be the same?

Consider the huge surface area of a steel-wool pad. It will displace much less water than a steel sphere of equal volume. Water displacement is *not* related to surface area.

Borek
Mentor
Consider the huge surface area of a steel-wool pad. It will displace much less water than a steel sphere of equal volume.
Define surface area of steel-wool pad.