Mica capacitors, Physics

Mica is a mineral that can be readily sliced into thin chips, makes an excellent dielectric and is used in capacitance incorporated in circuits requiring stable and accurate capacitors with low losses and high leakage resistance. Mica sheets are brittle and cannot be rolled up like a paper dielectric. The capacitor consists either of alternate layers of metallic foils, with mica forming a stack which is then hermetically sealed in some hard plastic or alternatively the mica can be silvered stacked and enclosed in a plastic moulding. The main characteristics of this type of capacitor are low power factor, high voltage operation and long term stability at room temperature. Precision mica capacitors, used as sub-standards Can be adjusted to better than 0.01 percent stability for values over 1μf. They are sealed in cases to protect against moisture. The silvered mica plate capacitor has a better temperature coefficient when compared to the stacked plate type. Both types exhibit slight non-cyclic capacitance shifts during temperature variation yielding a nonlinear temperature capacitance characteristics.

Specifications

Capacitance range                                    1pf to few micro farad

Ratings                                                    up to 2000V

Temperature                                             550C to 1250C

Dielectric constant                                     8

Power factor                                             approx 0.0003 at 1 MHz

Applications: They are used in filter circuits and tuning circuits.

 

 

Posted Date: 7/9/2012 6:39:19 AM | Location : United States







Related Discussions:- Mica capacitors, Assignment Help, Ask Question on Mica capacitors, Get Answer, Expert's Help, Mica capacitors Discussions

Write discussion on Mica capacitors
Your posts are moderated
Related Questions
What is common end? The fiber or fibers should be connected to the illuminator. Particularly in the case of a number of fibers, these have to be bunched together and contain se

A uniform ring has a radius R with centre C. A nd B are 2 pts on the circumference.such that angle theta is 60 0 .find the equivalent resistance between pt A and B? solution) le


What is a P-N junction? How does it behave under forward and reverse bias?  Describe with the help of circuit diagrams.

How do you make a model of a free body diagram for a science project?

Two point changes q1 and q2 are placed at a distance r from one another then electrostatic potential energy of two phase charge system will be kq 1 q 2 /r  . We take P.E. of two ch

A spacecraft is moving relative to the earth An observer on earth finds that , according to her clock 3601s elapse between 1pm and 2pm on the spacecraft''s clock. what is the space

The humidity of air can be determined by use of two different thermometers; a 'dry bulb' thermometer and a 'wet bulb' thermometer.  With reference to a suitable text book, explain

Determine the HVL of photons in air, water, muscle, bone, and Pb for energies of 5 keV, 100 keV, 1 Mev and 100 MeV and then fill in the table below. Note that you must find the HVL

These materials are used for permanent magnet manufacturing because of their low cost and their low weight. It consists of low iron oxide in combination with either barium carbonat