B Generator shaft rotation through spring and magnet (Is this feasible in Physics?)

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The discussion revolves around the feasibility of using a spring and magnet mechanism to run a generator powered by a battery. Participants express skepticism about the practicality of this idea, emphasizing that using a battery to power a generator does not effectively generate additional electricity. The consensus is that energy losses in the system would prevent any net gain, particularly when trying to charge the battery with the same energy source. They highlight that electric bikes typically harness energy from pedaling or braking rather than attempting to recharge the battery while in use. Overall, the concept lacks a viable application without addressing fundamental physics principles regarding energy transfer and loss.
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Hi Respected Teachers and Members ,

I would like to know that how can i run electrical generator through spring and magnet mechanism , The source can be battery to spring and magnet mechanism and spring and magnet mechanism run the shaft of generator and produce electricity

Thank you very much

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What is the point of this device? I can't think of a good reason to power a generator with a battery except to change the voltage or to turn the DC into some sort of AC power, and those don't typically use 'springs and magnets'. You're not thinking that this could be turned into some sort of perpetual motion device, are you?
 
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Drakkith said:
What is the point of this device? I can't think of a good reason to power a generator with a battery except to change the voltage or to turn the DC into some sort of AC power, and those don't typically use 'springs and magnets'. You're not thinking that this could be turned into some sort of perpetual motion device, are you?
In fact, this idea would work like this: generate electricity on an electric bike when the bike is in motion, we have to generate electricity to charge the battery, so wants to use the energy from the battery and run the generator and to have enough electricity to charge the battery.
 
Then the spring and magnets are not helpful. You want to just have the battery and the generator. When you want to charge the battery you take mechanical energy from the person, use the generator to convert it to electric power, and store it in the battery. When you want to assist the person you would simply run the same devices in reverse. You would discharge the battery, supply electric power to the motor and convert it to mechanical energy to assist the person. A motor is just a generator run in reverse
 
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Micheal_Leo said:
In fact, this idea would work like this: generate electricity on an electric bike when the bike is in motion, we have to generate electricity to charge the battery, so wants to use the energy from the battery and run the generator and to have enough electricity to charge the battery.
Obviously you cannot use the battery's electricity to charge itself, so I hope that's not what you were trying to do. You cannot even use the motion of the bicycle unless you're recovering energy during braking.
 
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Drakkith said:
Obviously you cannot use the battery's electricity to charge itself, so I hope that's not what you were trying to do. You cannot even use the motion of the bicycle unless you're recovering energy during braking.
how about If we connect battery to generator and have electricity so that we have less loss.
 
Micheal_Leo said:
how about If we connect battery to generator and have electricity so that we have less loss.
The only way you get less loss is if you use the generator for braking. This is the principle of hybrid automobiles.
 
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Micheal_Leo said:
how about If we connect battery to generator and have electricity so that we have less loss.
Let's say the battery outputs 100 watts to the circuit that includes the generator. The generator will receive 95ish watts thanks to losses in the battery and the rest of the circuit. Then the generator will output 90ish watts, again due to various losses (resistance, radiative losses, etc). Even if you feed that back to the battery you'll still have a net loss.
 
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Drakkith said:
Let's say the battery outputs 100 watts to the circuit that includes the generator. The generator will receive 95ish watts thanks to losses in the battery and the rest of the circuit. Then the generator will output 90ish watts, again due to various losses (resistance, radiative losses, etc). Even if you feed that back to the battery you'll still have a net loss.
yes indeed , losses are the factors that contribute to net output power to battery
 
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Micheal_Leo said:
yes indeed , losses are the factors that contribute to net output power to battery
I don't know what you're trying to say with this.
 
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  • #11
Drakkith said:
You cannot even use the motion of the bicycle unless you're recovering energy during braking

Electric bikes also use the energy from the rider, 'gently' pedalling on the flat and also the energy available when rolling downhill. It's like a savings account in the bank; regular small payments allow you to make big purchases once a year. (i.e. for going up a steep hill).

The extra load on your pedals to produce enough energy to be worth storing in the battery will be noticeable. I remember, as a lad, fitting two dynamos and an extra lamp to my bike and the effect of that was very noticeable; similar to storing a useful amount of energy for the motor, later. Nothing's free.

And, of course, whenever you transfer energy between battery and motor generator there is some loss.
 
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  • #12
if we attach axial flux generator with wheel of bike , we know that we have electricity but two problems i am facing that
1) when bike stop , the generator will stop and cut electricity to battery
2) the bike speed is 35km/h and the battery is 48v , so we need more than 48v to charge battery .the bike motion should be very fast every time to achieve more than 48v , so bike fast motion is also impossible
 

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  • #13
I'm not sure what to tell you that hasn't already been said. You cannot use the motion of the bike to charge the same battery you are using to power the bike, except during regenerative braking.
 
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