Assuming perfect health and no other problems, the reason the ears hurt when Scuba-diving, is because of inadequate equalization of the pressure in the middle ear during decent.
All parts of the body that "contain air" need to be pressurized while diving. But other bodyparts, like the sinuses and lungs, are automatically pressurized (lung pressurization only requires you to breathe). The ears are the only part that requires action on the divers part, and only on decent.
This is a basic part of any dive-course corriculum.
they get wet
Thus because the pressure out of your ear is much bigger than in it , so the air press your film of ear ,so you get hurt.
So that you don't risk bursting your eardrum, damaging other body air spaces, or even causing vertigo.
their is no air in the water
water pressure
Dive in the pool
because it makes the force make bigger and does notmove
It is extremely dangerous. If you hit your head on the bottom of the pool/sea bed, you can become a quadriplegic/paraplegic or possibly even die.
Dive in the pool
It depends on the altitude of your swimming pool. The ambient pressure will be relatively close at only 12 ft. no mater the altitude. If you were to ask whether it would hurt more at 30 ft. in a pool or in Lake Superior, then the altitude will be more of a factor. Lake Superior is appx 600 ft. above sea level, therefore, the baraometric pressure will be different than a pool at 15,000 feet above sea-level. In this senario, your ears would hurt more at 30 ft in Lake Superior than in a swimming pool at 30 feet. This is of course all assuming that by using the term "Ears Hurt" you mean where would they have more pressure, because as your ears equalize, they shuld feel the same at 12 feet underwater as 100 feet. tritonunderwater.com
swim laps, dive, backstroke
It shouldn't after all the top of the pebble tech pool is out of the water forever and it doesn't seem to hurt it. However be careful that you don't get a build up of ground water around the outside of the pool, This can cause an empty pool to start floating and that will definitely hurt it. If you have a hydro static valve at the bottom that works it should be ok.
sure does
It moves away from the human anatomy while u dive into the pool. This also decreases the viscosity in the water
fluid friction