Force on dielectric in parallel plate capicitor

AI Thread Summary
The force acting on a dielectric slab inserted between parallel plates of a capacitor is derived from the electrostatic force of attraction between the charges. This force can be calculated using the formula: [8.85 * 10^-12]b(k-1)(V^2)/2d, where b is the plate width, d is the distance between the plates, V is the potential difference, and k is the dielectric constant. The force remains constant even as the distance between the charges decreases because the overall system adjusts to maintain the potential difference, counteracting the expected decrease in force due to the inverse square law. The discussion emphasizes the importance of understanding the capacitor's geometry and the effects of inserting the dielectric. This analysis is crucial for applications involving capacitors and dielectrics in electrical engineering.
nik jain
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Force act on dielectric slab on inserting between the parallel plate = [8.85 * 10^-12]b(k-1)(V^2)/2d

where b = width of the plate , d = distance b/w the plates , V is the constant potential difference across the plates and k = dielectric constant

Which force is acting on dielectric slab in this case and who is acting this force on the slab and how this value comes ?
 
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nik jain said:
Force act on dielectric slab on inserting between the parallel plate = [8.85 * 10^-12]b(k-1)(V^2)/2d

where b = width of the plate , d = distance b/w the plates , V is the constant potential difference across the plates and k = dielectric constant

Which force is acting on dielectric slab in this case and who is acting this force on the slab and how this value comes ?

Hi nik jain!
What do you think which type of force should act?
To obtain this value of force, start by making a diagram of the capacitor when the dielectric is being inserted in the capacitor, suppose that x length of dielectric is inside the capacitor. The dimensions of capacitor are l and b. What is the equivalent capacity when the x length of dielectric is inside it.
 
I got it .

It is the electrostatic force of attraction b/w the charges .

One more question : Why its value remains constant as the distance(r) b/w the charges goes on decreasing and magnitude of force of attraction is inversely proportional to r^2 ?
 
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