Find the moment about the aa axis and the angles for max moment
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- čas přidán 1. 11. 2016
- The force of F = 30 N acts on the bracket as shown.
Determine the moment of the force about the a-a axis of
the pipe if a = 60, b = 60, and g = 45. Also, determine
the coordinate direction angles of F in order to produce the
maximum moment about the a-a axis. What is this moment? Get the book: amzn.to/2h3hcFq
5.408 N*m is the maximum moment in the question
howd you get this
@@Jimmiegame the same way he found the first moment, except now with different direction cosines.
goat
I have the same answer but negative, idk why. but since it's the max moment that is asked for this specific question, the answer should be higher than the other moment ofc, so you're right. just wondering why my calculator gives the same answer but then with a minus sign.
For the last part, from the given geometry of the problem, you can first :
-create a triangle with known side lengths of 0.1 m and 0.15 m, this will give you distance between points 0 and A.
-Once you have this distance, you can calculate the moment created about point A by using Moment = Force x distance
-Force = 30 N, given in the problem. Distance = .1802 meters, calculated by Pythagorean theorem ( 0.1m ^2 + 01.5m ^2 = distance OA^2)
Moment = F x d =======> M = 30 N x .1802 meters ========> 5.408 N m
u should make a video ill subsrcibe
for moment calculation can we shift the origin to another point for convenience or is that wrong?
bro how do you find components
Thank you for this! Although I'm kinda confused about the last part, "what is this moment?" was the first thing we found not the moment??
The question "what is this moment" may not be worded very well, It's asking for the moment of the force with the "new" angles. As we know, moment = m = (force perpendicular)(distance). You can find the distance by using Pythagorean's theorem, and the force perpendicular is given to you. Hope that helped (1 year late).
Why is the moment of aa added to 4.37?.Is'nt it in cartesian vector?
I have simple question, could you explain the reason we set the unit vector of a-a = j? Is that because it is on parallel line of y-axis? I hope someone could explain this....
You're exactly right. The unit vector of a-a is just j because that is the only direction a-a is in.
what is this moment
thank u sir for excellent lecture =amarjit = advocate =advocate -delhi high court --india
how would you write the moment in cartesian form?
you would have to multiply the magnitude of that moment with the unit vector that's along the axis you want the moment about, and if you want the moment about a point in the cartesian form, do the same thing but the unit vector should be from the point to any point on the force's line of action.
Thanks! I think you missed the last moment
how did you find Uy?
a-a is in the j direction only therefore, Uy is equal to 1j.
why do we have why if it's not playing any role pls explain i can't understand
why not
bless your soul
Thanks!
sir -u have to substract from 90 two times to find maximum
(-2.25)+(-2.12) is not positive. That would mean that the pipe rotates in the opposite direction. Knowing to change the sign from this method would mean intuitively knowing to change it not mathmatical computation so to speak. Would it not be correct to set A as the (0i+0j+0k) so that OA would be (-0.1i+0j+.15k). This would result in 4.37Nm being positive. Which again is the correct answer but without intuition.
what is the moment
the maximum moment of the system
that moment when