If the deeper you go underwater the higher the pressure becomes due to the weight of the water column on top of you, does that mean that the deeper something is the heavier it becomes? For example, if I’m above water on a boat and want to bring up a submerged object by pulling from a rope attached to it, would I have to pull the weight of the object PLUS the weight of the water on top of it? I figure this would mean that past a certain depth it would become impossible to pull something up back to the surface no matter how small it is, which sounds like nonsense to me but I could obviously be wrong.
In: Physics
No. Good thinking, but the water also presses on the bottom of the object (and the sides).
In fact it pushes on the bottom of the object slightly more than it does the top (since the bottom is deeper, and theres more water above it, so greater pressurr), so the net effect is that the water actually helps you pull the object out, and it is effectively lighter.
Thats what *buoyancy* is. Water always pushes up on something more than it does down, and so always makes it lighter.
Have you ever tried to push something like a basketball underwater? It shoots right back upwards, because the bouyant force on the ball is greater than the weight from gravity of the ball. If it only pushed it down like you suggest then it would sink.
You can also see yourself that things feel lighter when they’re underwater. For example its very easy to lift a person when they’re underwate
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