Explanation:
The net force of each square is the combination of the forces in each direction. The direction is the... direction the square would go in due to the net force. The magnitude of the net force is how large it is. So if you had a force pushing 2N to the left and 1N to the right, then the net force would be 1N to the left; because the two oppose eachother. If they were going in the same direction, then they'd add to each other. And perpendicular net forces (like one pushing up and another pushing left) can create net forces in diagonal directions.
I'm not going to do all of these for you because they're basically all the same thing and it's good practice for you anyway. But I'll do the first three just so you can get the idea:
1. The net force's magnitude is 4N and it's direction is to the right.
2. The net force's magnitude is 4N and it's direction is to the left.
3. The net force's magnitude is 0N and it has no direction because they are equal forces acting in opposite directions.
Answer:
<em><u>Gravitational</u></em><em><u> </u></em><em><u>force</u></em><em><u> </u></em><em><u>is</u></em><em><u> </u></em><em><u>1</u></em><em><u>.</u></em><em><u>3</u></em><em><u>3</u></em><em><u> </u></em><em><u>×</u></em><em><u> </u></em><em><u>1</u></em><em><u>0</u></em><em><u>^</u></em><em><u>-</u></em><em><u>9</u></em><em><u> </u></em><em><u>N</u></em>
Explanation:


Answer:

Explanation:
Let consider that pipe is a horizontal cylinder. The Nusselt number is equal to:
, for
.
Where
is the Rayleigh number associated with the cylinder.
The Rayleigh number is:

By assuming that air behaves ideally, the coefficient of volume expansion is:



The cinematic and dynamic viscosities, thermal conductivity and isobaric specific heat of air at 10 °C and 1 atm are:




The Prandtl number is:



Likewise, the Rayleigh number is:


Finally, the Nusselt number is:
![Nu = \left\{0.6+\frac{0.387\cdot (12.486\times 10^{6})^{\frac{1}{6} }}{\left[1 + \left(\frac{0.559}{0.733}\right)^{\frac{9}{16} }\right]^{\frac{8}{27} }} \right\}^{2}](https://tex.z-dn.net/?f=Nu%20%3D%20%5Cleft%5C%7B0.6%2B%5Cfrac%7B0.387%5Ccdot%20%2812.486%5Ctimes%2010%5E%7B6%7D%29%5E%7B%5Cfrac%7B1%7D%7B6%7D%20%7D%7D%7B%5Cleft%5B1%20%2B%20%5Cleft%28%5Cfrac%7B0.559%7D%7B0.733%7D%5Cright%29%5E%7B%5Cfrac%7B9%7D%7B16%7D%20%7D%5Cright%5D%5E%7B%5Cfrac%7B8%7D%7B27%7D%20%7D%7D%20%20%5Cright%5C%7D%5E%7B2%7D)

Iron, cobalt, and nickel are elements with a magnetic field.