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NOTE: This video will appear in a playlist on Smarter Every Day hence the references to Veritasium. Destin does lots of cool science stuff – check out his channel.
There several types of engines that give lift and power the aerial platforms that can house a camera, two of them use propellers. i though it would be interesting to learn a bit about the laws of physics behind the mechanics. Here are some common terms used to describe the action of the physics.
Precession is a change in the orientation of the rotational axis of a rotating body. It can be defined as a change in direction of the rotation axis in which the second Euler angle (nutation) is constant. In physics, there are two types of precession: torque-free and torque-induced. -wikipedia.
Torque-free precession occurs when the axis of rotation differs slightly from an axis about which the object can rotate stably: a maximum or minimum principal axis.
Torque-induced precession (gyroscopic precession) is the phenomenon in which the axis of a spinning object (e.g., a part of a gyroscope) “wobbles” when a torque is applied to it, which causes a distribution of force around the acted axis.
And that is why planes fly
Did you find it?
he always finding new ways to make you shit your pants. in some videos he adds an extremely loud static noise at the end
Also note that although the MASS of the object does not change, the weight distribution of the object does change temporarily with the added rotational force.
Well it does, coz it wasn’t just multiplication. It was vector multiplication (known as vector product or cross product of vectors).
So, A X B is not equal to B X A where A & B are vectors.
Rather A X B = – B X A.
It’s multiplication, it doesn’t matter.
The vector equation you have written to express Torque as cross product of two vectors was wrong.
tau = r x F not F x r.
ANTI- CLOCKWISE?!
u sir are awesome. I Subbed
WOW, way to complicated…. I think you confused everybody! The resultant force of precession occurs at a position 90 degrees after the force is applied to a spinning disk in the plane of rotation….
I’m studying industrial engineering and I understand pretty well concepts as angular momentum, velocity fields and so on. However, I can’t understand where does the momentum that makes everything spin come from (a supposedly vertical upwards orientated vector).
This is not a complaint about the video (which undoubtedly many will find useful), it’s just me wanting to understand.
So cool
of course it does, air is only causing friction and slowing the rotation and thus the effect of defying gravity.
so i assume you understand the concepts of torque and angular momentum crytal clear, great if so.
only your dialect
LMFAO awesome ending i subscribed
Fascinating video. Thanks!
CONGRATULATIONS! You’ve earned a new sub 😀
We learned about this today in physics class. Also, is there a difference between counter-clockwise and anti-clockwise?
I did, then i looked for the top comment so i could like it.
Nice end
Check out Prof. Eric Laithwaite’s lecture on gyroscopes on google. Fun stuff.
The part where he was trying to point in the direction of the torque and angular momentum while keeping up with the wheel spinning was pretty funny.
i still jumped even after reading that comment xD
Ok, understood.
How about the force of gravity. Assume this system is in a vacuum on Earth. Also assume the whole system is friction-less. If one were to spin the wheel but the amount of torque they put in the system is not enough to overcome gravity, then it will eventually rotate side to side like a pendulum rather than displaying the behavior seen here. This is my hypothesis, and this is the other half of what I was thinking when I wrote the previous comment.
It does, indeed, work in vacuum, ie. in space. Rotating disks are an easy way to turn a spaceship, for instance. There’s nothing to do with air or other medium, it is just forces acting out on eachother.
wheelchair tire
i call that gravity fucking
It would work even better because you have no air creating friction to slow it down thus allowing the wheel to spin forever.
It would work in a vacuum, the wheel isn’t creating lift, watch the video again.
Does this work in a vacuum? I would assume not due the fact that you need air to push against the wheel as it rotates in order to keep it a float. But that is just a prediction.
I showed one of my friends the end, and she asked me what the video is about and why Derek “chopped off his head”… And she watched the rest of it…
I was expecting a beheading.
To transition into a Biology lesson.
jumped and squealed!
Thanks Derek. This is the best and simplest explanation of this non-intuitive phenomena I have seen. I especially like how you applied the principle to the static wheel first and showed it works for both non-spinning and spinning cases. Thanks!
why i have never seen this channel before? its awesome
I thought he died. He uploaded the video so clearly not. Science, bitches!
like and subscribe from saudi arabia..
Torque is the moment of force. Like the term ‘torque’ is only used for force, whereas moment is more general: you can have a moment of inertia, moment of momentum etc.
What is the different between moment and torque? I’m confused. Are they the same thing?
I feel the same way.. funny part is.. I, too, have English homework.
I should be doing my English homework. But who needs that when you wanna be a physicist?
It would just process in the opposite direction as the torque is now pointing away from you and the angular momentum to the right. So it will process clockwise in the horizontal plane.
yep
a change of momentum
hes not applying force, hes applying an impulse.
thats awesome
Put a high powered drill in your hand switch it in and start to man over your hand in a circular direction opposite to the direction of which the drill is turning while you finger is in the trigger….what you feel I’d opposite torque vector …and you feel a strange resistance which doesn’t want you to move you arm the way you have…TRY IT
That’s cool
What if you will rotate wheel in other direction?
did anyone else jump right at the end?? lol
coool