Because it depends on how much numbers are increasing into the element
Answer:
B. 2.3mm
Explanation:
The correct answer for the given question is B. 2.3mm. Some aircraft are made are fabricated from aluminium which has plane stain fracture toughness. In the given scenario the plane stain toughness is
Ktc = 40 [ MPa
]
When the Ktc increases the fracture will appear on the aircraft. In this case the maximum crack until the fracture failure is 2.5mm.
Answer:
Explanation:
Given:
Diameter of aluminum wire, D = 3mm
Temperature of aluminum wire, 
Temperature of air, 
Velocity of air flow 
The film temperature is determined as:

from the table, properties of air at 1 atm pressure
At 
Thermal conductivity,
; kinematic viscosity
; Prandtl number 
The reynolds number for the flow is determined as:

sice the obtained reynolds number is less than
, the flow is said to be laminar.
The nusselt number is determined from the relation given by:
![Nu_{cyl}= 0.3 + \frac{0.62Re^{0.5}Pr^{\frac{1}{3}}}{[1+(\frac{0.4}{Pr})^{\frac{2}{3}}]^{\frac{1}{4}}}[1+(\frac{Re}{282000})^{\frac{5}{8}}]^{\frac{4}{5}}](https://tex.z-dn.net/?f=Nu_%7Bcyl%7D%3D%200.3%20%2B%20%5Cfrac%7B0.62Re%5E%7B0.5%7DPr%5E%7B%5Cfrac%7B1%7D%7B3%7D%7D%7D%7B%5B1%2B%28%5Cfrac%7B0.4%7D%7BPr%7D%29%5E%7B%5Cfrac%7B2%7D%7B3%7D%7D%5D%5E%7B%5Cfrac%7B1%7D%7B4%7D%7D%7D%5B1%2B%28%5Cfrac%7BRe%7D%7B282000%7D%29%5E%7B%5Cfrac%7B5%7D%7B8%7D%7D%5D%5E%7B%5Cfrac%7B4%7D%7B5%7D%7D)
![Nu_{cyl}= 0.3 + \frac{0.62(576.92)^{0.5}(0.70275)^{\frac{1}{3}}}{[1+(\frac{0.4}{(0.70275)})^{\frac{2}{3}}]^{\frac{1}{4}}}[1+(\frac{576.92}{282000})^{\frac{5}{8}}]^{\frac{4}{5}}\\\\=12.11](https://tex.z-dn.net/?f=Nu_%7Bcyl%7D%3D%200.3%20%2B%20%5Cfrac%7B0.62%28576.92%29%5E%7B0.5%7D%280.70275%29%5E%7B%5Cfrac%7B1%7D%7B3%7D%7D%7D%7B%5B1%2B%28%5Cfrac%7B0.4%7D%7B%280.70275%29%7D%29%5E%7B%5Cfrac%7B2%7D%7B3%7D%7D%5D%5E%7B%5Cfrac%7B1%7D%7B4%7D%7D%7D%5B1%2B%28%5Cfrac%7B576.92%7D%7B282000%7D%29%5E%7B%5Cfrac%7B5%7D%7B8%7D%7D%5D%5E%7B%5Cfrac%7B4%7D%7B5%7D%7D%5C%5C%5C%5C%3D12.11)
The covective heat transfer coefficient is given by:

Rewrite and solve for 

The rate of heat transfer from the wire to the air per meter length is determined from the equation is given by:

The rate of heat transfer from the wire to the air per meter length is 
Answer:
False
Explanation: An unstable flow is a flow process where the properties of the flow is unstable, in this case the flow input and flow output are not equal.
Unstable flow is also known as transient flow process because the main properties of interest which includes the time of flow and the volume of the flow through the pipe is not the same so this type of low gives more concern to the person carrying out the study.