Angular to lenear motion

[whirlwindhorse]

Hello Edtharan, I cannot spell linear ha!

I enjoyed your answer to the hoverboard question back in February so I thought I would make you my first contact and post on this website. I'm creative but have no formal education however I have considered the basics of gyroscopic forces,angular momentun and procession, conservation of momentum, righthand rule ect...

My area of interst is angular momentun converted to linear momentum as result of collisions in order for momentum to be conserved, in general, so, since velocity is a vector, momentum is also a vector, pointing in the same direction as the velocity, of course. It turns out experimentally that in any collision between two objects (where no interaction with third objects, such as surfaces, interferes), the total momentum before the collision is the same as the total momentum after the collision. It doesn’t matter if the two objects stick together on colliding or bounce off, or what kind of forces they exert on each other, so conservation of momentum is a very general rule.

My question is can electric motors do enough work to accelerate enough mass in angular form to then be released in linear momentum to move a closed system through space by doing the work with electricity? does the equal and oppisite reaction somehow get absorbed in an angular form?

I,m looking for answer to the hoverboard ha.

Here is example of what I'm cosidering. momentum, was actually introduced by the French scientist and philosopher Descartes before Newton. Descartes’ idea is best understood by considering a simple example: think first about someone (weighing say 45 kg) standing motionless on high quality (frictionless) rollerskates on a level smooth platform. A 5 kg medicine ball is thrown directly at her by someone standing in front of her, and only a short distance away, so that we can take the ball’s flight to be close to horizontal. She catches and holds it, and because of its impact begins to roll backwards. Notice we’ve chosen her weight so that, conveniently, she plus the ball weigh just ten times what the ball weighs by itself. What is found on doing this experiment carefully is that after the catch, she plus the ball roll backwards at just one-tenth the speed the ball was moving just before she caught it, so if the ball was thrown at 5 meters per second, she will roll backwards at one-half meter per second after the catch.

It is tempting to conclude that the “total amount of motion” is the same before and after her catching the ball, since we end up with ten times the mass moving at one-tenth the speed but all things being equal if the person who threw the ball origanally is also on frictionless skates would they have moved backwards? and in equal momentum to the ball moving forward? (again conservation of momentum) so if the work done with the ball thrower was replaced with an electric motor spinning the ball angularly then releasing the ball linearly and the motor mounted on the platform and on rollerskates with frictionless bearings could the equal and oppisite reaction be converted to angular motion therefore hopefully moving a closed system through space by the ball catcher colliding wih a wall connected perpendicular to the platform and the platform also on rollerskates with frictionless bearings on a smooth floor with angular to linear momentum by having eleclectricty doing the work

or does the motor move backwards like the thrower would? and if hitting a wall also perpendicular to the platform would cause zero movement because of conservation of momentum all replies are appreciated.

I believe timing of the collisions with the walls could be a big consideration. The equal and oppiste reaction on a lenear plane is one of my biggest questions. I am just beginning to read and understand the angular momentum of a particle. If torque becomes a consideration I would say two identicle motors Spinning synchronously in opposite directions and shooting the ball simultaneously would hopefully counteract torque forces.

 

What is wrong or right with this idea? I will appreciate any input and debunking. like at the moment the ball is released is there an equal and opposite reaction on a linear plane? as far as the rotation of the (flywheel like launcher) does it speed up or slow down?

 

Could an electric space elevator be constructed?

 

 

 

al best

 

whirlwindhorse

Edited June 21, 2008 by whirlwindhorse
idea clarification ver:3

[Royston]

Could an electric space elevator be constructed?

 

Because you didn't use paragraphs, I gave up after the first few sentences, but a space elevator is being planned (see the link)

 

http://www.space.com/businesstechnology/technology/space_elevator_020327-1.html

[Edtharan]

Hello Edtharan, I cannot spell linear ha!

Hi, and thanks. (oh and to help spelling I use the spelling checker that you can get for Firefox, works a treat and comes in several languages too).

 

so if the work done with the ball thrower was replaced with an electric motor spinning the ball angularly then releasing the ball linearly and the motor mounted on the platform and on rollerskates with frictionless bearings could the equal and oppisite reaction be converted to angular motion therefore hopefully moving a closed system through space by the ball catcher colliding wih a wall connected perpendicular to the platform and the platform also on rollerskates with frictionless bearings on a smooth floor with angular to linear momentum by having eleclectricty doing the work

The problem with this is that the example with the roller-skates throwing the ball is not exactly a closed system.

 

With the roller-skates, they are free to get further and further apart as time goes on. However, if they were connected together by a rope, then when the first skater threw the ball, they would be sent in the opposite direction, but then would then tug on the rope and pull the second skater in that direction too.

 

Then when the ball was caught be the second skater, this would end up stopping the second skater and this would pull on the rope and stop the first skater too.

 

Now if the skaters wanted to return the ball to the firs skater so that they could throw it again, the would be the same as when the first skater threw the ball, only now it is in the opposite direction. The result is that both skaters and ball end up in the exact same place as when they started.

 

or does the motor move backwards like the thrower would? and if hitting a wall also perpendicular to the platform would cause zero movement because of conservation of momentum all replies are appreciated.

A spinning device also follows the conservation of momentum. If I start something spinning (say an electric motor) in a clockwise direction, there is an equal and opposite force pushing the motor housing in the anticlockwise direction.

 

You can actually feel this in those small electric toy car motors. When you turn on the motor you can feel the casing try to spin in the opposite direction.

 

You can break the vectors of rotation up into two separate and linear vectors. One is at a tangent to the direction of rotation. The other is at 90 degrees to this and pointing in the direction of rotation. As this creates a change in the vector, this equates to an acceleration around the shaft of rotation.

 

It is this "acceleration" that give us the "Centripetal Force" that we experience as we rotate (like when going around a corner in a car).

 

When you add the vectors of all these, suing rotation to fling an object away from the motor, it will cause the same equal and opposite reaction to the motor as if you just threw the object by hand.

 

The only way you could use this to get a net movement is to have an open system where you leave something behind (like the balls, or exhaust form a rocket or jet).

[whirlwindhorse]

Thank you for your answers, most people will not even try to consider my questions, I enjoy abstract thinking and maybe I should've gone to school. The good news is I'm still learning and curious. Thank you again for your great

reply. I am a videomaker, and someday I may use this type of communication on one of my video projects. You can check out some of my vids if you like at http://www.closeupvideos.com. I do videos for fun,ha.

 

al best

 

whirlwindhorse

[Edtharan]

Thank you for your answers, most people will not even try to consider my questions,

If someone is genuinely interested in learning, then their is no such thing as a stupid question.