Second moment of area about an axis along any diameter in the plane of the cross section (i.e. x-x, y-y) is each equal to (1/4)pi r^4.
The second moment of area about the zz-axis (along the axis of the cylinder) is the sum of the two, namely (1/2)pi r^4.
The derivation is by integration of the following:
int int y^2 dA
over the area of the cross section, and can be found in any book on mechanics of materials.
Answer:
c- translation
Step-by-step explanation:
it just moved a few points down
Answer:
k = 10
Step-by-step explanation:
The triangles angels added up must equal 180 degrees, and the top angle is 65 degrees by the 180 degree rule.
So 10k + 15 must equal the remaining 115
subtract 15 from each side and you get 10k = 100
divide each each by 10 and you get the answer of k = 10
Answer:
C) a positive correlation
Step-by-step explanation:
<em>More people ⇒ Longer time</em> is a positive correlation between those variables. However, <em>longer time</em> is not the desired outcome.
Rather, <em>shorter time</em> is the desired outcome. The correlation between <em>more people</em> and <em>shorter time</em> is negative. In order to compute that correlation numerically, one would have to define a function that would give a numerical value for "shorter time" that would model the goodness of outcome as time gets shorter.
So you have a pole that is 10 feet tall that has a rope that goes from the top to the ground, the rope being 30 degrees to the ground... You can draw a right triangle using these dimensions. Now that you have a triangle, you look at where your 30degree angle is related to the side whose length you know and the side whose length you wish to find. The side you know is opposite from the 30 degrees while the side you want to find is the hypotenuse, for it goes down at an angle. You will use the opposite and hypotenuse sides, so, according to SOH CAH TOA, you will be using sin.
![\frac{opposite}{hypotenuse}=sin\theta,\theta=30,opposite=10,hypotenuse=?](https://tex.z-dn.net/?f=%5Cfrac%7Bopposite%7D%7Bhypotenuse%7D%3Dsin%5Ctheta%2C%5Ctheta%3D30%2Copposite%3D10%2Chypotenuse%3D%3F)
plug in those values and solve for your hypotenuse.
The easiest way to do this is if you knew the identities for special right triangles like the 30 60 90 triangles or the 45 45 90 triangles, but I showed you how to solve for your sides even if they're not special