Equal and opposite forces with electricity

In summary: Energy is conserved and does not change in an electrical system. In summary, the 3rd law of thermodynamics states that the total energy in an isolated electrical system will always be dissipated as heat. There is no net force on the system.
  • #1
fragiggle
1
0
I have a question concerning the generation of electricity and equal and opposite forces.
I've been having a hard time describing it. Sorry if I don't get my point across.
If I start off with using a generator to generate charge in capacitors, I have the equal and opposite forces being the work done by the generator and the charge in the capacitors. Then I take a system such as a rail gun where current is the direct cause of the forward momentum.
Then I had the question, if I have saved up work to balance an equal and opposite force with my charge in the capacitor. Wouldn't losing charge be the balancing factor in the recoil of a rail gun? but then I found this source and it states.

"Recoil forces in EM railguns appear wherever the
breech of the railgun is closed electromagnetically.
This means recoil forces may appear on power supply
leads, switches, or power supply components them-
selves. Careful attention is required on the part of
the railgun designer to control the location of the
recoil loading and provide means for sustaining the
loads. Careless design can result in undesirable
forces being applied to the projectile armature as
well. On the other hand a thorough understanding of
where and how recoil forces are generated can be used
to good advantage in some EM gun systems. In closing
we offer aspiring railgun designers one bit of advice
originally offered to HPG machine designers bys by Hr. B.
0. Lamme in 1906, 'You can't fool the flux.' " But now I am stuck with what is the balancing force of the discharge of the capacitors? Or if I removed the capacitors and had a powerful enough generator to fire a rail gun, what would be the balancing force of the generator? like I am putting force in and getting a projectile out. before it was the static force between the capacitors increasing.

I guess I'm stuck thinking that the energy dissipated by the capacitors would equal the kinetic energy of the projectile plus the heat lost and the force on the rails. then I just don't see any magnetic fields crossing current to cause any recoil.

Or does the projectile really just push back on the field and that pushing back is translated back into the system? does anyone know the equations for that if this is indeed what happens?
 
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  • #2
You appear to be confusing energy and force descriptions.
To understand the 3rd law force pairs in electrical systems, you need to describe the effects purely in terms of electrical and other forces.
 

1. What is the concept of equal and opposite forces with electricity?

The concept of equal and opposite forces with electricity is based on Newton's third law of motion, which states that for every action, there is an equal and opposite reaction. In the context of electricity, this means that when an electric charge is applied to a conductor, an equal and opposite charge is induced in the opposite direction.

2. How does equal and opposite forces with electricity affect circuits?

In a circuit, equal and opposite forces with electricity are essential for maintaining balance and stability. When a current flows through a circuit, the electrons experience a force in one direction, and an equal and opposite force is applied to the circuit elements, such as resistors and capacitors, to maintain equilibrium.

3. Can equal and opposite forces with electricity cancel each other out?

Yes, in some cases, equal and opposite forces with electricity can cancel each other out. This is known as a balanced force or a neutralized charge. It occurs when two opposite charges or forces are exerted on an object, resulting in a net force of zero. In this case, there is no movement or change in the object's motion.

4. How do scientists measure equal and opposite forces with electricity?

Scientists measure equal and opposite forces with electricity using a unit called the Coulomb (C). This unit measures the amount of electric charge and is equivalent to the charge of 6.24 x 10^18 electrons. The direction of the force is determined by the direction of the electric charge, with opposite charges attracting each other and like charges repelling each other.

5. What are some real-life examples of equal and opposite forces with electricity?

One example of equal and opposite forces with electricity is the operation of a battery-powered flashlight. When the battery is connected to the flashlight, an electric current flows, and equal and opposite forces are exerted on the electrons in the circuit. This results in the production of light. Another example is the attraction and repulsion of charged objects, such as a balloon sticking to a wall or hair standing up after being rubbed with a balloon.

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