Confused with pressure in closed-box

  • Thread starter Thread starter kbuild
  • Start date Start date
  • Tags Tags
    Confused Pressure
AI Thread Summary
In a closed box scenario, the pressure acting on ball A is indeed equal to the atmospheric pressure (Patm) outside the box. The confusion arises from the assumption that the closed nature of the box isolates the ball from external pressure influences. However, since the box is rigid and sealed, the pressure inside the box remains equal to the atmospheric pressure acting on it. The air mass above the box does not directly affect the ball, but the pressure is transmitted through the walls of the box. Therefore, the pressure on ball A is Patm, as it is not isolated from the external atmospheric conditions.
kbuild
Messages
3
Reaction score
0
I'm confused when i consider about this picture in my head.

... imagine that there is a ''closed-box'' on the floor.
And ball A is in this closed-box.
Pressure acted on the box = Patm.

I'm wondering, how much pressure act on ball A ?

With my sense, i think it is Patm.
... but i can't explain! it's a closed-box, so air mass above the box should have no effect on the ball in box ?!
 
Physics news on Phys.org
If the box is rigid and sealed from the surrounding air, then the outside pressure shouldn't affect the ball inside.
 

Thread 'Average velocity as a weighted mean'

Hello everyone, Consider the problem in which a car is told to travel at 30 km/h for L kilometers and then at 60 km/h for another L kilometers. Next, you are asked to determine the average speed. My question is: although we know that the average speed in this case is the harmonic mean of the two speeds, is it also possible to state that the average speed over this 2L-kilometer stretch can be obtained as a weighted average of the two speeds? Best regards, DaTario
View full post »

Thread '1:1 versus 2:1 Mechanical Advantage debate'

The rope is tied into the person (the load of 200 pounds) and the rope goes up from the person to a fixed pulley and back down to his hands. He hauls the rope to suspend himself in the air. What is the mechanical advantage of the system? The person will indeed only have to lift half of his body weight (roughly 100 pounds) because he now lessened the load by that same amount. This APPEARS to be a 2:1 because he can hold himself with half the force, but my question is: is that mechanical...
View full post »

Thread 'Newton's first law?'

Some physics textbook writer told me that Newton's first law applies only on bodies that feel no interactions at all. He said that if a body is on rest or moves in constant velocity, there is no external force acting on it. But I have heard another form of the law that says the net force acting on a body must be zero. This means there is interactions involved after all. So which one is correct?
View full post »

Similar threads

"Air Pressure" is not "the weight of the air above you"
Replies
27
Views
4K
Does Pressure in Phase Diagram refer to vapor pressure?
Replies
27
Views
6K
Question about pressure inside closed flask
Replies
7
Views
4K
Calculating Filling Time for a Diving Tank with Changing Hydrostatic Pressure
Replies
2
Views
2K
Pressure differential and air flow
Replies
13
Views
6K
I Sound pressure and inverse distance law
Replies
5
Views
2K
How does a Western free reed work? (musical instruments)
Replies
12
Views
3K
I Ways to put n balls in m boxes such that exactly k boxes are empty?
Replies
29
Views
3K
Exactly how do pressure waves work at the molecular level?
Replies
49
Views
4K
I Find Best Water Nozzle Type & Pressure for Longest Distance
Replies
32
Views
9K

Hot Threads

Recent Insights

Back
Top