Force that holds capacitor plates

AI Thread Summary
A capacitor's plates experience an attractive electrostatic force due to their opposite charges when connected to a battery, which raises questions about the forces maintaining their mechanical equilibrium. The plates are typically secured by a frame or dielectric material, preventing collapse, but concerns arise when air acts as the dielectric and weak connections are used. The energy dynamics of the system indicate that as the plates move closer, the total energy decreases, which is energetically favorable. Despite the small magnitude of the electrostatic force, the plates may still move towards each other, influenced by factors like inertia and friction. Demonstrations, such as those at the Exploratorium, illustrate the movement of charged objects under electrostatic forces.
akhil123
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For any capacitor, whose 2 plates or conductors are being held by a battery to a constant potential difference of V volts, there is a force of attraction between the plates, since they are oppositely charged. What is the force that 'holds' these conductors at their respective positions i.e. what is the force that maintains mechanical equilibrium of each plate?
 
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akhil123 said:
What is the force that 'holds' these conductors at their respective positions i.e. what is the force that maintains mechanical equilibrium of each plate?
The capacitor plates aren't just floating in mid-air. They are usually attached to a frame or the space between them is filled with some material.
 
The dielectric slab will prevent the plates from collapsing onto each other...but what if the dielectric is air? And if the wires used to connect the conductors to the remaining circuit are weak copper strands? I am asking this because,when the net energy change for the (battery+capacitor) system is calculated when plates move nearer because of this attractive force, the total energy of the system decreases, and decrease of energy is always favourable for any system to achieve.
 
The electrostatic force is pretty small, but yes the capacitor plates will move towards each other. Depending on inertia, friction, air movement, etc, they may or not come into contact. At the Exploratorium in San Francisco we had a big box with two thread loops hanging from the top, one a bit shorter than the other so they couldn't "collide", you could charge up the threads with the same or opposite polarities of static electricity and watch them move.
 
Thanks a lot!
 
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