Answer with Explanation:
Stress is defined as the force acting per unit area on a material.
Mathematically
![\sigma =\frac{dF}{dA}](https://tex.z-dn.net/?f=%5Csigma%20%3D%5Cfrac%7BdF%7D%7BdA%7D)
where
is the stress ,
is an infinitesimal force that acts on an infinitesimal area ![dA](https://tex.z-dn.net/?f=dA)
When a body is under stress it's dimensions change and this change in dimensions is known as strain.
Mathematically
![\epsilon =\frac{\Delta x}{X}](https://tex.z-dn.net/?f=%5Cepsilon%20%3D%5Cfrac%7B%5CDelta%20x%7D%7BX%7D)
where
strain in the object
is the change in any dimension of the body
Now in the above relation of stress, the area involved also changes when the body is loaded as the load produces strain which changes the dimensions of the body.
Now while calculating the stress if we use the original area of the cross section of the body prior to loading the stress that we calculate is the engineering stress and the strain associated with it is the engineering strain.
On the other hand if we use the true cross section of the body when it is loaded the stress that we calculate is the true stress and the strain associated with it is the true strain.
Mathematically they are related as
![\epsilon _{true}=ln(1+\epsilon _{engineering})}](https://tex.z-dn.net/?f=%5Cepsilon%20_%7Btrue%7D%3Dln%281%2B%5Cepsilon%20_%7Bengineering%7D%29%7D)
Thus the true stress is found to be larger than engineering stress.
Answer:
The answer is D. Society (the public)
Explanation:
Codes of ethics state the engineer's duties to society, to employers, to clients, to colleagues, to subordinates, and to the profession. However, when these duties conflict, which group should take precedence? a. Employers and clients b. Colleagues and subordinates. c. The profession. d. Society (the public)
The answer is D. Society (the public)
did it help ? I was going to put the same things so
Answer:
Explanation:
Given that:
v(t) = 339.4 sin(377t + 90°) V
i(t) = 5.657 sin (377t + 60°) A
v = 339.4 ∠ 90° ![v_m \angle\phi_1](https://tex.z-dn.net/?f=v_m%20%5Cangle%5Cphi_1)
i = 5.657∠60° ![I_m \angle \phi_2](https://tex.z-dn.net/?f=I_m%20%5Cangle%20%5Cphi_2)
The phase difference
= 30
The average power
can be expressed as:
![P_{avg} = \dfrac{v_m}{\sqrt{2}}\dfrac{I_m}{\sqrt{2}} \times cos (30)](https://tex.z-dn.net/?f=P_%7Bavg%7D%20%3D%20%5Cdfrac%7Bv_m%7D%7B%5Csqrt%7B2%7D%7D%5Cdfrac%7BI_m%7D%7B%5Csqrt%7B2%7D%7D%20%5Ctimes%20cos%20%2830%29)
![P_{avg} = \dfrac{339.4}{\sqrt{2}}*\dfrac{5.657}{\sqrt{2}} \times cos (30)](https://tex.z-dn.net/?f=P_%7Bavg%7D%20%3D%20%5Cdfrac%7B339.4%7D%7B%5Csqrt%7B2%7D%7D%2A%5Cdfrac%7B5.657%7D%7B%5Csqrt%7B2%7D%7D%20%5Ctimes%20cos%20%2830%29)
![\mathbf{P_{avg} = 831.38 \ watts}](https://tex.z-dn.net/?f=%5Cmathbf%7BP_%7Bavg%7D%20%3D%20831.38%20%5C%20watts%7D)
The reactive power Q is as follow;
![Q = \dfrac{v_m}{\sqrt{2}} * \dfrac{I_m}{\sqrt{2}} \ sin \phi\\](https://tex.z-dn.net/?f=Q%20%3D%20%5Cdfrac%7Bv_m%7D%7B%5Csqrt%7B2%7D%7D%20%2A%20%5Cdfrac%7BI_m%7D%7B%5Csqrt%7B2%7D%7D%20%5C%20sin%20%5Cphi%5C%5C)
![Q = \dfrac{339.4}{\sqrt{2}}*\dfrac{5.657}{\sqrt{2}} \times sin (30)](https://tex.z-dn.net/?f=Q%20%3D%20%5Cdfrac%7B339.4%7D%7B%5Csqrt%7B2%7D%7D%2A%5Cdfrac%7B5.657%7D%7B%5Csqrt%7B2%7D%7D%20%5Ctimes%20sin%20%2830%29)
Q = 479.99 VAR
The complex power S = P + jQ
The complex power S = 831.38 W + j479.99 VAR