Calculate E - capacitor question

  • Thread starter Thread starter blueyellow
  • Start date Start date
  • Tags Tags
    Capacitor
AI Thread Summary
The discussion centers on calculating the electric field (E) and electric displacement field (D) in a parallel plate capacitor filled with two glued dielectric materials. The capacitor has square plates with a distance d between them, much smaller than the plate side length L. The dielectrics have different constants and dimensions, affecting the electric fields in the regions they occupy, as well as in the vacuum between them. The user expresses frustration with their attempts to apply relevant equations, such as E=q/(epsilon0*A) and E=deltaV/d, indicating difficulty in progressing toward a solution. The conversation highlights the complexities of integrating the effects of multiple dielectrics in capacitor calculations.
blueyellow

Homework Statement



Consider a parallel plate capacitor with square plates of side L and distance d<<L apart. The bottom plate lies on the x-y plane, and the distance d is parallel to z. A block of dieletric material can completely fill the space between the plates.

Consider the dieletric to be composed of two materials glued together, material 1 with dieletric constant epsilon1 and dimensions 0.6L*L*d (in x, y and z directions, respectively) and material 2 with constant epsilon2 and dimensions 0.4L*L*d. The dielectric is free to move as a single block without friction along the x axis, parallel to the plates inside the capacitor, and it can also move outside the capacitor. Let us define as x the distance between the dielectric and the edge of the plates, and we can neglect the electric field outside the plates. Considering that the potential difference between two points a and b is delta V= integral from a to b of E.dl, and that D=epsilon0*epsilon(subscript r)*E, where epsilon(subscript r) is the dielectric constant, calculate the value of the electric field E and of the electric displacement field D in the region between the plates, for the three possible regions where the space is occupied by the material 1, the one with material 2, and the vacuum.

Homework Equations

 
Physics news on Phys.org
attempt at solution:

E=q/(epsilon0 *A)



E=deltaV/d

= integral from a to b of E.dl /d



E=-grad V



but all this seems to be leading nowhere.
 
TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...
Thread 'Variable mass system : water sprayed into a moving container'
Starting with the mass considerations #m(t)# is mass of water #M_{c}# mass of container and #M(t)# mass of total system $$M(t) = M_{C} + m(t)$$ $$\Rightarrow \frac{dM(t)}{dt} = \frac{dm(t)}{dt}$$ $$P_i = Mv + u \, dm$$ $$P_f = (M + dm)(v + dv)$$ $$\Delta P = M \, dv + (v - u) \, dm$$ $$F = \frac{dP}{dt} = M \frac{dv}{dt} + (v - u) \frac{dm}{dt}$$ $$F = u \frac{dm}{dt} = \rho A u^2$$ from conservation of momentum , the cannon recoils with the same force which it applies. $$\quad \frac{dm}{dt}...
Back
Top