i am confused about this physics question, please answer.?

Question

if a boy is drinking milk by a straw from a glass. p1 is the pressure at bottom of the glass p2 at the surface and p3 in the mouth then:
1)p3 is less than p1
2)p2 is less than p1
3)none

Please explain!!!!!!!!!!!!!!!!!!!!!

Answer 1

1: p3 is less than p1.

The previous posters statement is incorrect.
There is not a uniform pressure within the milk!

The milk at the surface only has air pressure pushing against it.

The milk at the bottom of the glass not only has the weight of the air pushing on it, it also has the weight of the milk on top of it exerting pressure.

Think of making a column of milk and air (say 20 miles into the atmosphere.) The pressure at any point in the column is equal to the weight of everything on top of it.

Anybody who has ever been in a submarine will tell you that pressure increases with depth -- that's what "crush depth" is all about!
.

Answer 2

OK. Let us break it up into smaller and simpler parts:

pressure inside a liquid is same. But when suction is applied by the boy by sucking on the straw, there is a temporary drop in pressure (p3 becomes momentarily less) and hence the atmospheric pressure pushes up the milk through the straw into the boy's mouth. So, p3 is less than p1 momentarily.

Answer 3

Haha, this concern cracks me up. besides, start up with the certainty that a watt is a joule in line with 2d. With that expertise you could decide how many joules the gardener expends in 20 minutes. Now, you comprehend the form of joules required, however the performance of intake is barely 50%, so that they are going to ought to consume two times the form of cherios that are corresponding to the joules they use to diminish the backyard. and then curiously they fall over and immobile, having expended their cheerio power grant.