Answer:
![Q=hA(T_{w}-T_{inf})=16.97*0.5(27-300)=-2316.4J](https://tex.z-dn.net/?f=Q%3DhA%28T_%7Bw%7D-T_%7Binf%7D%29%3D16.97%2A0.5%2827-300%29%3D-2316.4J)
Explanation:
To solve this problem we use the expression for the temperature film
![T_{f}=\frac{T_{\inf}+T_{w}}{2}=\frac{300+27}{2}=163.5](https://tex.z-dn.net/?f=T_%7Bf%7D%3D%5Cfrac%7BT_%7B%5Cinf%7D%2BT_%7Bw%7D%7D%7B2%7D%3D%5Cfrac%7B300%2B27%7D%7B2%7D%3D163.5)
Then, we have to compute the Reynolds number
![Re=\frac{uL}{v}=\frac{10\frac{m}{s}*0.5m}{16.96*10^{-6}\rfac{m^{2}}{s}}=2.94*10^{5}](https://tex.z-dn.net/?f=Re%3D%5Cfrac%7BuL%7D%7Bv%7D%3D%5Cfrac%7B10%5Cfrac%7Bm%7D%7Bs%7D%2A0.5m%7D%7B16.96%2A10%5E%7B-6%7D%5Crfac%7Bm%5E%7B2%7D%7D%7Bs%7D%7D%3D2.94%2A10%5E%7B5%7D)
Re<5*10^{5}, hence, this case if about a laminar flow.
Then, we compute the Nusselt number
![Nu_{x}=0.332(Re)^{\frac{1}{2}}(Pr)^{\frac{1}{3}}=0.332(2.94*10^{5})^{\frac{1}{2}}(0.699)^{\frac{1}{3}}=159.77](https://tex.z-dn.net/?f=Nu_%7Bx%7D%3D0.332%28Re%29%5E%7B%5Cfrac%7B1%7D%7B2%7D%7D%28Pr%29%5E%7B%5Cfrac%7B1%7D%7B3%7D%7D%3D0.332%282.94%2A10%5E%7B5%7D%29%5E%7B%5Cfrac%7B1%7D%7B2%7D%7D%280.699%29%5E%7B%5Cfrac%7B1%7D%7B3%7D%7D%3D159.77)
but we also now that
![Nu_{x}=\frac{h_{x}L}{k}\\h_{x}=\frac{Nu_{x}k}{L}=\frac{159.77*26.56*10^{-3}}{0.5}=8.48\\](https://tex.z-dn.net/?f=Nu_%7Bx%7D%3D%5Cfrac%7Bh_%7Bx%7DL%7D%7Bk%7D%5C%5Ch_%7Bx%7D%3D%5Cfrac%7BNu_%7Bx%7Dk%7D%7BL%7D%3D%5Cfrac%7B159.77%2A26.56%2A10%5E%7B-3%7D%7D%7B0.5%7D%3D8.48%5C%5C)
but the average heat transfer coefficient is h=2hx
h=2(8.48)=16.97W/m^{2}K
Finally we have that the heat transfer is
![Q=hA(T_{w}-T_{inf})=16.97*0.5(27-300)=-2316.4J](https://tex.z-dn.net/?f=Q%3DhA%28T_%7Bw%7D-T_%7Binf%7D%29%3D16.97%2A0.5%2827-300%29%3D-2316.4J)
In this solution we took values for water properties of
v=16.96*10^{-6}m^{2}s
Pr=0.699
k=26.56*10^{-3}W/mK
A=1*0.5m^{2}
I hope this is useful for you
regards
Radio waves are radiated by charged particles when they are accelerated. They are produced artificially by time-varying electric currents, consisting of electrons flowing back and forth in a specially-shaped metal conductor called an antenna. ... Radio waves are received by another antenna attached to a radio receiver.
Answer:
D. a triangle and a T-Square
Explanation:
A T-Square is the best drawing tool to create squares. You would need a squares to create cubes.
Answer
Statically determinate beams are those beams in which the unknown reaction forces are equal or less than the equilibrium equation.
As shown in figure 1 in which reaction forces are 3 and we have 3 equilibrium equation so beam is determinate.
Statically indeterminate beams are those beams in which unknown reaction force are more than the equilibrium equation.
As shown in figure 2 in which reaction forces are 6 and we have 3 equilibrium equation so beam is indeterminate.