What do you mean by 3 dB cutoff frequency? Why is it 3 dB,
not 1 dB?
Answers were Sorted based on User's Feedback
Answer / ashish
None of you has explained, what happens if I take 4 dB or 5
dB point.
Every one knows that at 3 dB point, power becomes half....so
what?
Is This Answer Correct ? | 0 Yes | 1 No |
Answer / john lam
A filter's cutoff frequency is generally, but not
necessarily based on the type of filters, defined at -3dB.
At this point, the voltage of the input has attenuated to
70.71%, or in power form 50%. After this point, the voltage
of the input will drop dramatically rendering it useless.
Therefore the -3dB point is picked as the cutoff frequency
point because of this nature. It's not chosen randomly.
*** Sorry, last one has typo errors by mixing up the two
percentages. This one is correct.
Is This Answer Correct ? | 0 Yes | 1 No |
Answer / sigma 6
The question is only asking, why not any integer between 0
and 3 Db.
Answer No.5 grips the teory of the question, and answer no.
6 Explains the applicability for the question.
Is This Answer Correct ? | 2 Yes | 16 No |
Answer / yesodha
3db value is the mean square value which is 70% of the
maximum value. the bandwidth found by using rms value will
be accurate
Is This Answer Correct ? | 27 Yes | 47 No |
Answer / vasmatkar@hotmail.com
Mrudula at some extent you are correct can you pls make it
more clear
Is This Answer Correct ? | 8 Yes | 40 No |
Answer / mrudula
3db implies 70%(o.7o7) of the power,i'e we r interested to
consider the bandwidth range from peak to 70% b'coz uptp
70% its reliable.hence 3db is called as half power freq
Is This Answer Correct ? | 73 Yes | 111 No |
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2 Answers BSNL, MCI, NPCIL, Sail,
dummy strain guage
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