How it is that when we go deeper in water(seas or oceans) the pressure increases, while water(generally liquids) are incompressible?

  • $\begingroup$ Look up: 'Pascal's Law' $\endgroup$
    – Gert
    Nov 9, 2015 at 1:06

1 Answer 1


The pressure is caused by the weight of the water above. The compressibility (or lack thereof) of water is irrelevant to the pressure.

Try this experiment. Put your hand on the table. Now put a brick on your hand and feel the pressure. Then add a second, third, etc brick. You will feel the pressure increase, but you will not see the bricks being compressed. It's exactly the same effect with water, or with the atmosphere for that matter: the pressure is caused by the weight of the material above.

  • $\begingroup$ So it is not really the pressure that increases, it is the weight?? Which as a result makes high pressure on things and people underwater?? $\endgroup$ Nov 9, 2015 at 1:15
  • $\begingroup$ is this right?? $\endgroup$ Nov 9, 2015 at 1:19
  • $\begingroup$ No, the pressure does increase. Pressure is force per unit area. For a specific amount of area, the pressure is the weight of a column of water with that area, going to the top of the surface. So the pressure and the weight are the same. Because the water is incompressible, the molecules aren't a lot closer together under the increased pressure, but that doesn't mean the pressure isn't increased. $\endgroup$ Nov 9, 2015 at 3:13

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.