If water is kept in vessels of different volumes, at the same level, the base area of each vessel being equal, then will the force experienced by the base of all the vessels be same? If so, why?
The forces experienced by the two bases are indeed the same. From a physical perspective, we can consider the standard gravitationally-induced pressure equation:[math]P = \rho g h[/math]Assuming the two vessels are filled with the same fluid (i.e. the fluids' densities are equal), the pressures are the same for both vessels, because the heights are the equal. Since both bases have the same area, and P = F/A, the forces on the bases are therefore equal.Why is this the case?Well, let's consider one vessel to be a typical cylinder (the easiest case), and the other vessel a truncated cone (that is, take an upside-down cone, and chop off a smaller cone from the bottom such that the base of the small cone's area is smaller than the area of the base of the large cone).Given that the bases are of equal area and the fluid is filled to the same height in both vessels, it is clear that the volume of fluid held in the truncated cone is greater than that in the cylinder.This gives rise to the question: Why are the forces on the bases equal when there are different masses of fluid pressing on them?Well, you need to consider the walls of the vessel. In the cylinder, the gravitational force of the fluid molecules never contacts the walls, as the force is parallel to these walls. In the truncated cone, however, part of the gravitational force of the molecules not adjacent to the base contacts the walls. This means only a portion of the total volume's gravitational force actually affects the base.As it so happens, you can determine this portion by looking at the column of fluid directly above the base, which happens to be a volume and shape equal to the cylindrical vessel.When you calculate the force on an object at the bottom of the ocean, you can calculate it by considering the gravitational force on the column of water directly above the object, sort of like the cylindrical vessel. The same thing applies to calculating atmospheric pressure and the force of air molecules pushing down on us. You just consider the gravitational force on the column of air above us.
Tough physics evaporation problem, I need help!?
A 5000 kg African elephant has a resting metabolic rate of 2500 W. On a hot day, the elephant's environment is likely to be nearly the same temperature as the animal itself, so cooling radiation is not effective. The only plausible way to keep cool is by evaporation, and elephants spray water on their body to accomplish this. If this is the only possible means of cooling, how many kg of water per hour must be evaporated from an elephant's skin to keep it at a constant temperature? I have no idea how to do this problem... If you need it the specific heat of elephant is 3400 J/kg*K In the book it does mention the heat of vaporization of water at 30 degrees Celsius is 24x10^5...but it doesn't mention that in the problem. I dunno if that helps... Junk/spam answers will be flagged...serious answers only please. Thanks!!
Temple feels swollen and keeps twitching?
also feels like my thumb is twitching, and my eyelid feels the same way, no other symptoms all on left side, havent been getting a lot of sleep throat hurts as well
Why would someone wake up dehydrated but have to urinate?
I understand that people need to urinate periodically to clean out their system but it's also used to help keep a constant level of water in the body. For a long while I would go to sleep and wake up dehydrated. I decided that it must be because I was losing water via sweat over night so I tried drinking a glass or two of water before going to bed but all that resulted in was waking up dehydrated AND needing to visit the restroom (sometimes even waking me up a few hours before my alarm to do so.) So why would my body feel dehydrated when it has plenty of water stored up in the bladder? And what can I do to not wake up dehydrated in the morning since drinking water before I go to sleep doesn't seem to be working.
Explain role of collecting duct in controlling water content of body fluids?
It participates in electrolyte and fluid balance through reabsorption and excretion, processes regulated by the hormones aldosterone and anti-diuretic hormone. The collecting ducts, particularly the outer medullary and cortical collecting ducts, are largely impermeable to water without the presence of anti-diuretic hormone (ADH). 1- In the absence of ADH, water in the renal filtrate is left alone to enter the urine, promoting diuresis. 2- When ADH is present, aquaporins allow for the re-absorption of this water, thereby inhibiting diuresis.
When a ship is moving on seawater and it enters a river and moves inland, is it expected to rise, sink or maintain the same level of draft?
Buoyancy! The upthrust on a body is equal to weight of the volume of the liquid displaced by that body. The density of sea water is more than river water because of presence of a number of salts dissolved in it. The average salinity of the oceans is 35gms per 1000ml of water. When the ship enters the sea, the water is no more the river fresh water but the saline sea water which is denser. As a result the weight of water displaced is now more than what it was previously when the ship was in river. The upthrust increases and the ship rises up.
An ice cube contains an iron ball in it and floats in water contained in a vessel. What will happen if ice melts away?
When an ice cube with a iron ball inside floating on water melts, the level of water will decrease.To understand why this is so let us consider the action of the ice and the ball separately.The ice floats on water because it has lower density than water. When ice is put in water it displace a volume of water which weighs same as the weight of ice. After melting, the volume of ice becomes same as that of the water that it was displacing. Therefore, there is no change in level of water due to melting of ice.Now let us examine effect of iron ball. The combined density of ice and iron ice is still less than that of water. That is why the ice cube with ball floats. In this case, additional volume of water displaced due to weight of metal piece, weighs same as the weight of ball. This is more than the volume of ball which has higher density than water. When the ice melts, the iron ball no longer is able to float above water and sinks. At this time the the volume of water displaced by the metal piece that has sunk is equal to just the volume of ball. Thus the volume of water displaced by ball reduces on melting of ice. Therefore, the level of water will reduce after melting of ice.Please note that, if at any time, before complete melting of ice, the ball embedded in ice sinks in the water, temporarily the level of water will rise. The exact amount of rise will depend on the remaining quantity of ice, If only the ball sinks, but the ice cubes remains floating, then also the water level will reduce to the same level as after complete melting of ice.Hope, that helps!