Lecture notes
Flashcards for 21.6 Capacitance
- Institution
- OCR
Flashcards for 21.6 Capacitance
[Show more]
Connected book
Book Title:
Author(s):
- Edition:
- ISBN:
- Edition:
Seller
Follow
Content preview
Q: Power and capacitorsA:
Capacitors are compact and can be charged easily to store energy
Unlike chemical cells, capacitors cannot store a great deal of energy in a small volume
However, capacitors can release the stored energy very quickly and thus generate a
high output of power
This is exactly what happens in a camera flash
You can store about a joule of electrical energy in a normal capacitor
o And when this is released in a time of 1ms, you get a power output of
about 1kW
Q: A rectifier circuit
A:
Q: Smoothing capacitors
A:
Domestic electricity is supplied as AC
o The direction of the current changes rapidly and repeatedly as the
supply voltage cycles from positive to negative and back
The simple rectifier circuit changes an alternating input voltage to a smooth direct
voltage
The diode allows current in only one direction only
Without the capacitor, the output voltage from the circuit would consist of positive
cycles only
With the capacitor, the output voltage is smoothed out and becomes almost direct
voltage of constant value
The ripple in the output voltage can be kept small by making the time constant of the
circuit much greater than the period of the alternating voltage
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller dylanval. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for £5.99. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
75759 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy revision notes and other study material for 14 years now