Answer:
stress = 8,556 Psi. or (stress = 59 Mpa)
Explanation:
stress = force / area
force P = 3 tons (convert to lbs. for units consistency)
1 ton = 2240 lbs.
P = 6,720 lbs.
steel bar Diameter D = 1 in. (convert to d
Area of steel bar = (π * 1²) / 4 = 0.785 in²
therefore, stress = 6720 lbs. / 0.785 in²
stress = 8,556 Psi.
in Mpa ----- 8556 Psi * 0.00689476 MPa/Psi = 59 Mpa
Answer:
Explanation:
The rank of the magnitude of the diffusion coefficient from greatest to least is as follows:
C in Fe at 900°C > Cr in Fe at 900°C > Cr in Fe at 600°C
Reason
C in Fe is an interstitial impurity while Cr in Fe is a substutional impurity.Therefore interstitial impurity occurs in C in Fe systems,while substutitional diffusion occurs in Cr in Fe system.Interstitial is much faster than substitutional diffusion hence the order
Also with increasing temperature magnitude of diffusion coefficient increases,due to the relation.
D = D₀exp(-Qd/RT)
Where D₀=Temperature independent per exponential
Qd= The activation energy for diffusion
R= Universal gas constant
T=absolute temperature