What is the correct area to use in a stress calculation for a compressed object?

  • Thread starter Thread starter 1question
  • Start date Start date
  • Tags Tags
    Area Mechanics
Click For Summary
In stress calculations for a compressed object, the correct formula is σ = F/A, where A represents the cross-sectional area being compressed. The confusion arises from whether to use A or 2A, but only the area of one side in contact with the force is relevant. The force F is applied uniformly across the area A, leading to the stress being calculated as the force divided by that single area. Understanding that A is the cross-sectional area clarifies the calculation. Therefore, the appropriate approach is to use σ = F/A for accurate stress determination.
1question
Messages
66
Reaction score
0

Homework Statement



In a simple mechanics question, which area should be used for a stress calculation? ex. A brick is compressed on 2 sides (opposite to each other) by a given compressive force F. The area of each of the sides being compressed is A.

Homework Equations



σ = F/A

The Attempt at a Solution



I'm just confused if it should be σ = F/A OR σ = F/(2A) and why.
 
Physics news on Phys.org
It's just σ = F/A. I forgot that A is cross-sectional area.
 

Thread 'Magnitude of buoyant force in fluids of different densities'

The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?
View full post »

Similar threads

How Does Fusing Beams with Different Properties Affect Stress Distribution?
  • · Replies 10 ·
Replies
10
Views
3K
Torsion and stress on a beam question
  • · Replies 9 ·
Replies
9
Views
2K
Confusion Calculating Young's Modulus
  • · Replies 5 ·
Replies
5
Views
2K
What Are the Assumptions and Calculations for Sheet of Charge Theory?
  • · Replies 1 ·
Replies
1
Views
1K
Bending Stress on a Protective Cover
  • · Replies 1 ·
Replies
1
Views
1K
Should I Use the Total Length of an Object to Calculate Buoyancy?
  • · Replies 10 ·
Replies
10
Views
11K
Internal stresses of an accelerating body
  • · Replies 11 ·
Replies
11
Views
3K
How Do You Calculate Compressive Stress in a Square-Sectioned Support?
  • · Replies 1 ·
Replies
1
Views
1K
Compression of a spring by an object in free fall
  • · Replies 8 ·
Replies
8
Views
3K
Compression of human bone: forces
  • · Replies 2 ·
Replies
2
Views
6K