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Old 04-16-2019, 08:05 PM
bistander bistander is online now
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Join Date: Apr 2015
Posts: 1,610
absolutely NOT right

Quote:
Originally Posted by Rakarskiy View Post
You absolutely correctly noticed that there is no load, no torque response. The mechanics of torque can be compared to electric amperes in a conductor. The calculation is made by a guy for potential energy.
This is a massive flywheel, a product and a system of magnets on the rotor flywheel and gear shift levers. In fact, no matter what he pushes, an electromagnet or a lever with a magnet. The main thing is that the magnets melt in a circle, and not closer to the device shaft. So the guy from the video is absolutely right, and he has an understanding.

https://youtu.be/UbWkIKgehLI

https://youtu.be/1bA2OMRcxKo
How can you say that guy in that video is right? He uses T = M * g * r for the torque developed by the rotor. Tell me how that is even remotely connected to that equation.

It's possible there is confusion due to similarly of units of torque and energy. This should help.

Quote:
"The units for torque, as you stated, are Newton-meters. Although this is algebraically the same units as Joules, Joules are generally not appropriate units for torque.

Why not? The simple answer is because

W=F⃗ ⋅d⃗
where W is the work done, F⃗ is the force, d⃗ is the displacement, and ⋅ indicates the dot product. However, torque on the other hand, is defined as the cross product of r⃗ and F⃗ where r⃗ is the radius and F⃗ is the force. Essentially, dot products return scalars and cross products return vectors.

If you think torque is measured in Joules, you might get confused and think it is energy, but it is not energy. It is a rotational analogy of a force.

Per the knowledge of my teachers and past professors, professionals working with this prefer the units for torque to remain N m (Newton meters) to note the distinction between torque and energy.

Fun fact: alternative units for torque are Joules/radian, though not heavily used."
https://physics.stackexchange.com/

And what do the two videos you linked have to do with the bad math guy?

bi
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