I watched thousand of videos to understand the vector and mainly and z-index. I took me times. It does not mean it will move into thumb direction, it means it will point at it!
It's hard to find a rational explanation of the right hand rule. It is not enough for me to merely say "then, because of the right hand rule" I want to know WHY? Bozeman, can you please explain next time?
Boze, nice vid and info. However, concerning the declination of Polaris: it's not exactly 90 degrees. It's around 89 degrees and 16 minutes, in J2000. So, it's only approximately located near the north equatorial celestial pole. *If you timelapse Polaris with a pro telescope properly aligned to a δ of 90 degrees then Polaris also rotates inside the eyepiece.* (which usually has a field of one degree or 30 minutes, depending on magnification)
Hi, can you explain why angular velocity is a vector. In other words why can we take it that when we add angular velocity of an object around the x axis to its angular velocity around the y axis and its angular velocity around the z axis, that we get the body's overall angular velocity around whatever axis it is rotating. What is the physical demonstration or intuition behind this. For linear velocity, it's obvious physically that adding the velocity in the x direction to that in the y direction to that in the z direction gives you the overall linear velocity of the body. So linear velocity is obviously a vector. There is nothing obvious about adding angular velocities. So why do we take it on faith that it is a vector. You might say because it has a magnitude and direction. But angular rotation has a magnitude and direction and angular rotation is not a vector (since it does not commute- composing rotations in different orders gives different resultant rotations, as we know). So back to why angular velocity is a vector? Mathematically you can represent angular velocity around the x, y and z axes as infinitesimal matrices and then show how infinitesimal matrices commute and how their product is also an infinitesimal matrix. So that shows that composing (in any order) matrix objects representing angular velocities around the x, y and z axes gives another matrix object representing some other angular velocity. This seems vector-like but how do we know that this resultant matrix object represents the actual angular velocity that we would get physically from adding the x, y, and z angular velocities?
Okay, so here is an experiment. And, what causes it? We mount two flywheels each on a different shaft. Mount them in the back of different pickups, with the shaft horizontal and parallel to the pickup length. We spin one flywheel CW and the other CCW. Then we accelerate the pickups forward, maintain side-by-side pickups. Theoretically the one spinning counter-clockwise should slow? Will the other one accelerate? What would happen the rotational velocities of the two?
Thanks for these videos :) I want to ask something.Does the rope's tension force which applies to object have any torque on the object.İ thought that spin occurs through with that rope tension force.
BomontiFiltresiz no, torque is only for rotating masses, otherwise it’s just force in the linear sense. The tension force up and mass gravity down are equal and holding it steady in one place.
Sal of Khan Academy says Angular Velocity is a pseudovector. Is that true? Other sources says as well, they say it is not a vector or a scalar? What is a pseudovector?
I watched thousand of videos to understand the vector and mainly and z-index. I took me times. It does not mean it will move into thumb direction, it means it will point at it!
It's hard to find a rational explanation of the right hand rule. It is not enough for me to merely say "then, because of the right hand rule" I want to know WHY? Bozeman, can you please explain next time?
Yeah I think the same.. It's so counter intuitive. I want to know exactly why
Me too
Me too! If the torque is in that direction, why isn't it moving towards that direction? Very very confusing!
Same with me
The best explanation I've got, it condensates the images and theory at once, thank you very much.
Boze, nice vid and info. However, concerning the declination of Polaris: it's not exactly 90 degrees. It's around 89 degrees and 16 minutes, in J2000. So, it's only approximately located near the north equatorial celestial pole. *If you timelapse Polaris with a pro telescope properly aligned to a δ of 90 degrees then Polaris also rotates inside the eyepiece.* (which usually has a field of one degree or 30 minutes, depending on magnification)
Thanks Paul this was eagerly awaited vdo.for a long time.
Thanks for the video.
Its funny when i was in school i never really enjoyed learning the same way i do now.
This is the only video where i find exact explanation of ...why direction of angular displacement, velocity, acceleration is in direction of thumb..
Why?
This is a lifesaver for my mechanics exam tomorrow.
Why is angular velocity or acceleration perpendicular to plane??? Please explain
Hi, can you explain why angular velocity is a vector. In other words why can we take it that when we add angular velocity of an object around the x axis to its angular velocity around the y axis and its angular velocity around the z axis, that we get the body's overall angular velocity around whatever axis it is rotating. What is the physical demonstration or intuition behind this.
For linear velocity, it's obvious physically that adding the velocity in the x direction to that in the y direction to that in the z direction gives you the overall linear velocity of the body. So linear velocity is obviously a vector. There is nothing obvious about adding angular velocities. So why do we take it on faith that it is a vector.
You might say because it has a magnitude and direction. But angular rotation has a magnitude and direction and angular rotation is not a vector (since it does not commute- composing rotations in different orders gives different resultant rotations, as we know).
So back to why angular velocity is a vector? Mathematically you can represent angular velocity around the x, y and z axes as infinitesimal matrices and then show how infinitesimal matrices commute and how their product is also an infinitesimal matrix. So that shows that composing (in any order) matrix objects representing angular velocities around the x, y and z axes gives another matrix object representing some other angular velocity. This seems vector-like but how do we know that this resultant matrix object represents the actual angular velocity that we would get physically from adding the x, y, and z angular velocities?
Okay, so here is an experiment. And, what causes it? We mount two flywheels each on a different shaft. Mount them in the back of different pickups, with the shaft horizontal and parallel to the pickup length. We spin one flywheel CW and the other CCW. Then we accelerate the pickups forward, maintain side-by-side pickups. Theoretically the one spinning counter-clockwise should slow? Will the other one accelerate? What would happen the rotational velocities of the two?
Best video ever..thank you so much !!!
Why the force of the gravity makes it move towards you and not away. i mean if the giroscope was spinning the other way would it make a diference?
Thanks for these videos :) I want to ask something.Does the rope's tension force which applies to object have any torque on the object.İ thought that spin occurs through with that rope tension force.
BomontiFiltresiz no, torque is only for rotating masses, otherwise it’s just force in the linear sense. The tension force up and mass gravity down are equal and holding it steady in one place.
Sal of Khan Academy says Angular Velocity is a pseudovector. Is that true? Other sources says as well, they say it is not a vector or a scalar? What is a pseudovector?
Can you make the next video of how genes transfer. Explaining the experiment of Griffth.
I love u man. Ur awesome
yes, this was helpful
Great
私は、表向き裏向きの遠心力の考えです。
Thanks you sir