Experiment shows that two perfectly neutral parallel metal plates separated by a small distance d sttract eachother via a very weak force, known as the Casimir force. The force per unit area of the plates, F, depends only on the Planck constant h, on the speed of light c, and on d. Which of the following has the best chance of being correct for F?

The charges on two parallel copper plates separated by a small distance are +Q and -Q . A test charge q experiences a force F when placed between these plates. Now if one of the plates is removed to infinity, then the force on the test charge will become :

The Casimir effect describes the attraction between two unchanged conducting plates placed parallel to each other in vacuum. The astonishing force ( predicted in 1948 by Hendrik Casimir) per unit area of each plate depends on the planck’s constant (h), speed of light (c) and separation between the plates (r). (a) Using dimensional analysis prove that the formula for the Casimir force per unit area on the plates is given by F= k (hc)/(r^(4)) where k is a dimensionless constant (b) If the force acting on 1xx1 cm plates separated by 1 mu m is 0.013 dyne, calculate the value of constant k.

Two large metal plates with surface charge densities +sigma and -sigma are separated from each other by a distance of d. Find the force per unit area acting between them.

Two long conducting wires are placed parallel to each other at a distance d. Current carried by the wires is i_(1)" and " i_(2) . If F is the force acting between them, per unit of length, then which of the following statments is true?

A parallel plate capacitor has two plates of area A separated by a small distance d. The capacitor is charged to a potential difference of V and the battery is disconnected. A metal plate with area A and thickness (d)/(2) is fully inserted between the plates, so that it always remains parallel to the plates. (a) Calculate the work done on the metal slab while it was inserted. (b) Does the two plates of the capacitor attract of repel the metal plate that is being inserted. Does the answer obtained in part (a) help you in answering this ?

A certain transmission line (very long) is constructed from two thin metal plates (parallel to each other) of width b, which are separated by a very small distance ‘h’ lt lt ‘b’ . The current travels down one strip and back along the other, and it is distributed uniformly over the surface of the plates as shown in figure. Neglect fringing field at ends of plates. Capacitance per unit length of this combination is

Two identical smooth disc of radius R have been placed on a frictionless table touching each other. Another circular plate is placed between them as shown in figure. The mass per unit area of each object is sigma , and the line joining the centers of the plate and the disc is theta (a) Find the minimum horizontal force F_(0) that must be applied to the two discs to keep them together. (b) Angle theta can be changed by changing the size of the circular plate. Find F_(0) when theta rarr 0 . [use "cos"theta = 1 - (theta^(2))/(2) and "sin"theta = theta "for small" theta ] (c) Find F_(0) when theta rarr (pi)/(2) . Explain the result .