# The Naked Scientists Forum

### Author Topic: Can a ring launcher be used as space propulsion?  (Read 1503 times)

#### ScientificSorcerer

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##### Can a ring launcher be used as space propulsion?
« on: 15/09/2014 06:27:07 »
Ring launchers and space propulsion

Many of you have probably seen the ring launcher experiment in high school or on the internet recently.  It's quite a cool and simple little demonstration illustrating the basics of electromagnetic induction. But could a similar device be used to propel space craft of the future?

If you are unfamiliar with the ring launcher then take a quick look at this video demonstration:

I had this idea were a space craft is propelled using a magnetic rod and an electromagnetic ring.

Imagine this...

You are in a space ship in micro gravity.  Your space craft is not a rocket, instead your spaceship is round like a ball and there is a thick neodymium rod going right through the middle of the ball, around the rod is an electromagnetic ring coil connected to a capacitor bank. when you push a button the electromagnetic ring gets flung at high speed into the top of the space craft and slams into it like a hammer hitting an anvil (with great kinetic energy) then a small reversed current slowly places the ring back on the other-side of the rod to repeat the process over and over again.

so all you have in your ship essentially is an over-sized ring launcher in the belly of your ship.  When the electromagnet hits the top of the ship at high speed it produces a force in that direction giving you the power to push yourself through space getting faster and faster with each pulse eventually getting near light speed.

This concept is very simplified so that everybody can understand but its basic enough to get the point across.  What do you think about this propulsion type.

As an added note, this propulsion method is not intended to get ships off the ground, instead it would only be used in space to make orbital adjustments and accelerate without the need for fuel.

It's greatest function of this is to be able to accelerate a space ship with only electricity.  A propulsion system of this type could never run out of "fuel", it could only run out of electricity which can be recharged by solar panels.

#### evan_au

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##### Re: Can a ring launcher be used as space propulsion?
« Reply #1 on: 15/09/2014 12:54:10 »
Unfortunately, the rapid acceleration for a short time creates exactly the same velocity change to the spacecraft as the slow restoring force for a much longer time - only in the opposite direction. The two actions cancel each other. Momentum is always conserved in any closed system.

To give the spacecraft an overall velocity change, you must accelerate the ring right away from the spacecraft. But fairly soon you will run out of rings (reaction mass).

Rather than carry a supply of rings and solar cells to power the electromagnet, chemical rockets combine the energy source (chemical energy) with the reaction mass (the products of the chemical breakdown). The higher the temperature, the more efficient the rocket - but chemical reactions are easily able to reach higher temperatures than rocket casings can withstand.

To get really efficient rocket motors, you need extremely high velocities for the reaction mass.  Ignoring solar sails (which reflect photons),  the current winners in this race are some form of ion rocket.

#### The Naked Scientists Forum

##### Re: Can a ring launcher be used as space propulsion?
« Reply #1 on: 15/09/2014 12:54:10 »