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Question:

how do i make a circuit with capacitor timed discharge?

so i wanna make a linear accelerator for a project im a first year engineering student and i have some capacitors, and i have the tube n coil made now i have a button switch and i can use 1 capacitor to accelerator a projectile, but i want to use multiple capacitors to accelerator the projectile so what i wanna do is have those coils at different parts in the tube and i want each capacitor to discharge when the projectile gets to it in the tube so that capacitor activates its magnetic fieldso how cud i create a circuit that timely discharges creating the magnetic field n accelerating the projectile?

Answer:

Interesting, but whatever you are accelerating needs to be detected so that you dump the power when it is halfway past the coil for each coil in the chain. See the links below for more information. The first is a 1.25kJ coilgun video. The second has theory and design considerations with references and bibliography, and the third is a free program to design coilguns with multiple coils and components. You should understand that your accelerator will do fine with magnetic materials, like iron projectiles but will do little or nothing for charged particles. For that you need a different form of accelerator with static charges that keep moving ahead of the particles and changing behind them. (To accelerate a proton, negative ahead and positive behind, for example). To understand the movement of charged particles versus magnetic fields, you need to be capable of calculating curl, which requires some vector mechanics and partial differential equations--a bit more than first year students are taught. Finally, any such circuit has resistance (R), inductance (L), and capacitance, (C). With those three components alone you have an RCL circuit which is roughly described by the second-order ordinary differential equation: d^2I/dt^2+(R/L)dI/dt+(1/L)I0 Which is good for a steady source voltage only. The magnetic flux is proportional to dI/dt
How fast is this projectile going to move? More significantly, what kind of time delay are you looking for? Like, is it milliseconds? Microseconds? Sub-microsecond? If the projectile is not moving too fast, then I would consider using a microcontroller to do the timing. With some clever hardware and software design, it might even be possible to sense the presence of the projectile by measuring the coil current or by photoelectric means, and have the algorithm _learn_ the optimum timing. If the timing is too fast for a microcontroller to handle, then how about using the projectile itself as the time base? Have the push button fire the first coil, as it already does, and have the other coils triggered by opto-sensors further on down the pipe. Beyond that, I don't know. High-speed analog-y kinds of circuits are beyond my ken.

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