Estimating Pressure on a Person Standing on the Ground

  • Thread starter Thread starter jumbogala
  • Start date Start date
  • Tags Tags
    Fluids Pressure
AI Thread Summary
To estimate the pressure exerted by a person standing on the ground, the force is calculated using the person's weight, which is the product of mass and gravitational acceleration. The area of contact with the ground, typically the area under the feet, is needed to determine pressure using the formula F = PA. The discussion clarifies that this problem does not involve air pressure or fluid dynamics, focusing solely on the pressure exerted by the person's weight on the ground. Participants emphasize the importance of estimating the area for accurate calculations. Overall, the pressure estimation is a straightforward application of basic physics principles.
jumbogala
Messages
414
Reaction score
4

Homework Statement


What pressure does a person standing on the ground exert?

Homework Equations


The Attempt at a Solution


This has something to do with fluids, but I'm not sure what!

I think I should model the person as a cylinder and find the pressure on the person, then find what the pressure is on the ground?

I really have no idea, that was just a guess. I don't know how to find the pressure on the person either...

Can anyone please get me started?
 
Last edited:
Physics news on Phys.org
Okay so I found this F = p*a
 
Last edited:
The force would be her weight (not her mass) and the area would be the one under her feet. Find the pressure.
 
I think I'm confused about the set up of the problem.

Force = 80 kg * 9.81 m/s^2

Area = area of top or bottom of cylinder?

then use F = area * pressure to find pressure?

So this has nothing to do with air pressure at all? Just confused because it's in with a bunch of other problems dealing with pressures from fluids, and I thought maybe air pressure contributes somehow.
 
The way I understand it, it has nothing to do with fluid. Just estimate the area under the feet of Emma (that's why the problem ask for an estimation of the pressure) and then use F = PA.
 
I multiplied the values first without the error limit. Got 19.38. rounded it off to 2 significant figures since the given data has 2 significant figures. So = 19. For error I used the above formula. It comes out about 1.48. Now my question is. Should I write the answer as 19±1.5 (rounding 1.48 to 2 significant figures) OR should I write it as 19±1. So in short, should the error have same number of significant figures as the mean value or should it have the same number of decimal places as...
Thread 'A cylinder connected to a hanging mass'
Let's declare that for the cylinder, mass = M = 10 kg Radius = R = 4 m For the wall and the floor, Friction coeff = ##\mu## = 0.5 For the hanging mass, mass = m = 11 kg First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on. Force on the hanging mass $$mg - T = ma$$ Force(Cylinder) on y $$N_f + f_w - Mg = 0$$ Force(Cylinder) on x $$T + f_f - N_w = Ma$$ There's also...
Back
Top