Guest

Why does a capacitor act as a short circuit ? Why does it act as an open circuit ? Please explain me clearly !!

Why does a capacitor act as a short circuit ? Why does it act as an open circuit ?
Please explain me clearly !!

Grade:12

1 Answers

SAGAR SINGH - IIT DELHI
878 Points
13 years ago

Dear student,

Real capacitors have a certain amount of inductance. This inductance keeps the capacitor from acting like zero ohms when sudden changes occur. Ceramic and mica capacitors have little inductance, and thus they act almost like zero ohms during sudden voltage changes. Tubular capacitors have more inductance, but this inductance is still quite small.

The wires supplying DC power to digital circuit boards have a certain amount of inductance that keeps current from flowing freely whenever the circuitry has a sudden demand for current. On such circuit boards, it's common practice to have two parallel capacitors connected across the DC supply lines. These capacitors are often referred to as decoupling capacitors (because they decouple the circuit board from the inductance present in the DC supply wires going to it). Such capacitors keep the DC voltage more constant than it would otherwise be.  They supply brief bursts of current when the digital circuitry switches on and off.

 

Please feel free to ask your queries here. We are all IITians and here to help you in your IIT JEE preparation.

All the best.

Win exciting gifts by answering the questions on Discussion Forum. So help discuss any query on askiitians forum and become an Elite Expert League askiitian.

Now you score 5+15 POINTS by uploading your Pic and Downloading the Askiitians Toolbar  respectively : Click here to download the toolbar..

 

Askiitians Expert

Sagar Singh

B.Tech, IIT Delhi

Think You Can Provide A Better Answer ?

ASK QUESTION

Get your questions answered by the expert for free