How do you calculate pressure using force and area?

dinhjeffrey
Messages
30
Reaction score
0

Homework Statement


http://img26.imageshack.us/f/1113001.jpg/

#16

Homework Equations



P=F/A


The Attempt at a Solution


F= 30N
A= πr^2
r= .01m
A = .0001π
P=F/A
P= 10^3 Pa
but the answer is E) 10^5 Pa
 
Physics news on Phys.org


What is 30/3.14 x 10^-4?

AM
 


95492 = 100,000 = 10^5 - oops miscounted the zeroes thanks lol
 

Thread 'Errors and significant figures'

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...
View full post »
Thread 'A cylinder connected to a hanging mass'

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...
View full post »

Similar threads

How to calculate pressure when two forces are exerted
Replies
23
Views
1K
Fluids: Concept about Fluid Pressure in a relation with Force and Area
Replies
6
Views
3K
What is the relationship between tire size and pressure changes?
Replies
13
Views
926
Pressure question: Weight of a car calculated from tyre contact patch area
Replies
3
Views
851
Understanding the Force of Two Cubes
Replies
1
Views
1K
How do you calculate the pull of this piston?
Replies
27
Views
1K
Magnetic energy density, and pressure due to magnetic force
Replies
23
Views
4K
Thermodynamics- Piston problem, pressure, internal energy
Replies
5
Views
2K
How Can I Solve This Fluid Dynamics Homework Problem?
Replies
3
Views
2K
Weakest Point of Cylinder in Pressure Piston Homework
Replies
6
Views
2K

Hot Threads

Recent Insights

Back
Top