The discussion centers around a problem involving a parallel plate capacitor with a dielectric material inserted between the plates. The original poster seeks to determine the force acting on the dielectric when it is near the edge of the capacitor, given specific parameters such as charge, dielectric constant, and dimensions of the capacitor.
The discussion is active, with participants confirming each other's calculations and clarifying the direction of the dielectric's insertion. There is a shared understanding of the approach to finding the force, although no consensus on the complete solution has been reached.
Participants note constraints such as the absence of an external power source and the assumption that the charge remains constant during the dielectric's insertion. There is also mention of difficulties in providing a diagram to illustrate the setup.
inserted how? From which direction?carlyn medona said:inserted to a distance x
Before or after the dielectric is inserted?carlyn medona said:if the capacitor has a charge q
Can you please show your detailed calculation? And a diagram would be helpful as well. Thanks.carlyn medona said:I found effective capacitance which was εw(kx+l-x)÷d and found force to be equal to q^2 d(k-1)÷(2εwl^2)
Assuming the insertion is in the length direction, that looks right to me.carlyn medona said:q^2 d(k-1)÷(2εwl^2)
But is that the "length" direction or the "width" direction? Judging from your reference to l-x it is the length direction.carlyn medona said:It was inserted from top
That's the method I used, getting the same result.carlyn medona said:found force by differentiating energy with respect to distance