Help with Science homework please?

Question

How can a woman wearing high heels exert a greater pressure than an elephant?

Why do the small bubbles exhaled by a submerged scuba diver get larger as they float to the surface of the water?
A unit of pressure is called a ___________

Why do you seem to weigh more in the air than in the water?

What is the definition of weight? What is the definition of mass?

Answer 1

The mass is distributed over a smaller cross sectional area (pressure is lbs/ square inch or Kg/square meter)

Because gasses expand as they rise. They stay the same temperature (basically) and lose few molecules to the water so they must expand in volume by PV=nRT

Units of pressure are many, PSI, millibars, Pascals, atmospheres to name 4

Archemedes Principle the closer in density two objects are, the more bouyancy the less dense object experiences. We are mostly water. It is the air in our lungs and body that usually keep us afloat

Weight is the measure of mass under the acceleration of force (such as gravity). Mass is just a measure of how much matter there is for gravity (or any other force) to act upon. For examle, say you have a 10 Kg mass here on Earth. That mass ia accelerated by gravity at 9.8 m/s^2, so it's weight is 98 Newtons. On the moon, gravity is about 1/6 that of Earth, so the same 10 Kg mass weighs only about 19 Newtons.

Answer 2

A theoretical four hundred pound woman with high heels could exert more pressure than a 250 pound baby elephant with large feet, as the pressure is exerted in pounds per square inch. If the heels have a small surface area the pressure per square inch would be greater.
When a diver descends, the pressure on him increases one atmosphere for every 33 feet he goes down. Because the air he is breathing is compressed, the size of the bubbles will expand as they rise to the surface, because there is less pressure on top of them to compress them.
A unit of pressure is called a millibar. (Did you bring your textbook home with you tonight? I guess not.)
In water you have more buoyancy than in air. This means that it partially supports your weight by pushing up. If you are denser (meaning heavier than the weight of the volume of water you displace) you will sink, and that is why people with little fat and a lot of bone and muscle weight will sink. On the other hand if your overall density matches that of the water volume you displace, you are buoyant, and and can feel like you are flying through the water, neither rising or sinking. If you have a lot of fat and you want to go scuba diving, you will have to wear a weight belt with some heavy weights to allow you to sink. Since the neoprene suits are buoyant on their own, it doesn't take much fat to have to use a weight belt.

Answer 3

as a scuba diver surfaces the pressure is lower, so the bubbles expand, i think it's bernoullis principle. this is why you NEVER hold yor breath while diving, and this is how a lung can explode.

PSI-Pressure Per Square Ich, or Metric which is BAR

water is more dense than air.

mass is constant in any gravity

weight is dependent on gravity

W=mg

Answer 4

properly enable me only whip out the ole McDougal Littell Earth technological know-how e book I actually have in my closet o wait, maximum persons answering this don't have your textbook the questions will be fantastic

Answer 5

Smaller area

Lower pressure

Newton

Less density

Pull of gravity. Area object takes up