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Best regards
HP

 

What you have is a capacitor discharging through a coil which will have resistance.

Without getting into voltage, current and power, you ought to study the behavior of an RCL circuit.

http://en.wikipedia.org/wiki/RLC_circuit

 

for example, you have 1,5 V AAA battery , you wanna use that battery and create high voltage the fastest way possible . so that voltage output coming from the capacitor can give you enough power to create a magnetic pulse also powerful enough to move the mentioned magnet away. it doesn't matter how long that pulse lasts. also.. rephrazed , what capacitor has the shortest charge timing considering that you charging it with one 1.5 V AAA battery and also what kind of a coil I need for that ? long story short, how to create the strongest magnetic pulse you Can, with 1.5 AAA battery ? how to charge fast for high voltage that could create that magnetic pulse strong enough.. i don't know if it can be asked different, or can that be answered but thank's for trying .

 

for example, you have 1,5 V AAA battery , you wanna use that battery and create high voltage the fastest way possible .

Your parameters won't produce high voltage 'fast' no matter what technique you use. You just can't get around the old energy in = energy out equation, so you need to use a circuit that builds high voltage from the slow trickle on energy you'll be getting from your small battery. The camera flash unit you mentioned earlier is going to be the best/quickest way to do this.

so that voltage output coming from the capacitor can give you enough power to create a magnetic pulse also powerful enough to move the mentioned magnet away. it doesn't matter how long that pulse lasts.

The high voltage will be one short pulse. It has limited usage for mechanical work. Not really enough to bother with. Again, you run up against the immutable laws of physics.

also.. rephrazed , what capacitor has the shortest charge timing considering that you charging it with one 1.5 V AAA battery

The charging equation for a capacitor is T = RC, where R is the combination of circuit resistance and capacitance series equivalent resistance(ESR). So, R and C are the only determinants of charging time, thus no 'type' of capacitor will charge faster then another, except for consideration of ESR.

and also what kind of a coil I need for that ?

A coil is a coil is a coil. Selection of a coil is parametric, and depends on the required inductance, wattage, etc.

BTW, high voltage isn't required just to move a small magnet. You can probably just connect the battery to a coil of wire over an iron core and get a pretty good magnet-mover.

 

The capacitor that charges the fastest is one with low capacitance, e.g. 1pF

You are not going to get much energy from a 1pF capacitor.

\(Energy =\frac{1}{2}CV^2\)

 

Your parameters won't produce high voltage 'fast' no matter what technique you use. You just can't get around the old energy in = energy out equation, so you need to use a circuit that builds high voltage from the slow trickle on energy you'll be getting from your small battery. The camera flash unit you mentioned earlier is going to be the best/quickest way to do this.



The high voltage will be one short pulse. It has limited usage for mechanical work. Not really enough to bother with. Again, you run up against the immutable laws of physics.



The charging equation for a capacitor is T = RC, where R is the combination of circuit resistance and capacitance series equivalent resistance(ESR). So, R and C are the only determinants of charging time, thus no 'type' of capacitor will charge faster then another, except for consideration of ESR.



A coil is a coil is a coil. Selection of a coil is parametric, and depends on the required inductance, wattage, etc.

BTW, high voltage isn't required just to move a small magnet. You can probably just connect the battery to a coil of wire over an iron core and get a pretty good magnet-mover.

Yes, thank you. Short pulse is what i need (short strong pulse) , i know i can get a magnet the way you mentioned using only battery , but what i need instead is that short stronger pulse of magnetic force , instead of weak magnetic force with longer duration. this circuit board and the capacitor i have on it can charge up to 300 V. but the charging duration lasts longer, 3 or so sec, when charging it with the that battery . is there any capacitor that can charge faster with the same battery and give same amount of volts ?

 

is there any capacitor that can charge faster with the same battery and give same amount of volts ?

Absolutely not.

 

Your parameters won't produce high voltage 'fast' no matter what technique you use. You just can't get around the old energy in = energy out equation, so you need to use a circuit that builds high voltage from the slow trickle on energy you'll be getting from your small battery. The camera flash unit you mentioned earlier is going to be the best/quickest way to do this.



The high voltage will be one short pulse. It has limited usage for mechanical work. Not really enough to bother with. Again, you run up against the immutable laws of physics.



The charging equation for a capacitor is T = RC, where R is the combination of circuit resistance and capacitance series equivalent resistance(ESR). So, R and C are the only determinants of charging time, thus no 'type' of capacitor will charge faster then another, except for consideration of ESR.



A coil is a coil is a coil. Selection of a coil is parametric, and depends on the required inductance, wattage, etc.

BTW, high voltage isn't required just to move a small magnet. You can probably just connect the battery to a coil of wire over an iron core and get a pretty good magnet-mover.

I have more questions regarding this just to help me understand it better I have to ask questions like that , i hope that's not a problem. you do understand what i need now and that helps allot.

 

Absolutely not.

ok, that helps. does it charge faster if you increase the voltage ? if I put 2 bateries instead of one ,does it speed up the charging time ?

 

To decrease the charging time you have to increase the current.

Google RC Time Constant.

http://www.allaboutcircuits.com/vol_1/chpt_16/1.html

http://www.electronics-tutorials.ws/rc/rc_1.html

 

ok, that helps. does it charge faster if you increase the voltage ? if I put 2 bateries instead of one ,does it speed up the charging time ?

It's possible if you increase the current, you can speed up the time it takes for a converter to charge up high voltage. In that case, you would connect the batteries in parallel.

 

To decrease the charging time you have to increase the current.

Google RC Time Constant.

http://www.allaboutcircuits.com/vol_1/chpt_16/1.html

http://www.electronics-tutorials.ws/rc/rc_1.html

ok, that helps, now if I put more current in it will charge faster . and also , does the voltage effect the charging time at all ?

 

v

It's possible if you increase the current, you can speed up the time it takes for a converter to charge up high voltage. In that case, you would connect the batteries in parallel.

very helpful, thank's allot. now if i need it to charge in less time i just use more current , but that will not change the current spent ? I mean, the current spent in charging it will be the same as in charging it with less current ?

 

Generally, no if the converter is correctly designed and utilized. I can't guarantee if that would be so for the little camera circuits.

 

To decrease the charging time you have to increase the current.

Google RC Time Constant.

http://www.allaboutcircuits.com/vol_1/chpt_16/1.html

http://www.electronics-tutorials.ws/rc/rc_1.html

helpful , thank you. i have more to ask. increasing the current will only change time of charging it but it wont change the current spent, right?

 

I will come to the end of this silly questions soon i get these basic holes filed up. . if fastest charging doesn't effect the current spent. and i think it should not. now the next question would be how strong that pulse of magnetic force can be from 300 V. ? or how much voltage i need for that stronger pulse ? by stronger i mean, for example so it can kick a smaller magnet out of my hand.. it doesn't have to be exactly measured.

 

That I do not know. But consider this: Magnetic force arises from current, not voltage. As I stated earlier, high voltage is not required. For example, using a coil to produce a magnetic field, the resulting field is proportional to current, and number of loops in the coil. The voltage required would be what is needed to get the required current, using V=I*R where R is the resistance of the coil wire.

 

What do you mean by "current spent"?

The time to charge to 63% of the voltage is tau = R x C.

The time to charge to 99% 0f the voltage is 4tau =4 x R x C

The charge on the capacitor Q = C x V

The energy in the capacitor is E = ½CV^2

 

That I do not know. But consider this: Magnetic force arises from current, not voltage. As I stated earlier, high voltage is not required.

I was told before that higher voltage can create a stronger magnetic pulse using less current ?

 

That's incorrect. Look at my edits for post #37.