Electronics - RLC Circuits and Resonance - Discussion

2. 

What is the bandwidth of the circuit?

[A]. 31.8 Hz
[B]. 32.3 Hz
[C]. 142 Hz
[D]. 7.2 kHz

Answer: Option A

Explanation:

No answer description available for this question.

Lalit Garg said: (Nov 1, 2010)  
As Q=B.W/fr
so fr=1/(2pie*underroot of LC)
And Q=UNDERROOT OF L/(R*UNDERROOT OF C)
B.W=?

Vimal said: (Apr 4, 2011)  
How?

Maddy said: (Apr 21, 2011)  
@Lalit from ur formulas I got 142Hz ans.
Is that ri8?

Aysha said: (Apr 27, 2011)  
fr=BW*Q

Hussain said: (Jun 1, 2011)  
BW = fr/Q; ---- @Aysha: i agree with u
Q ---- quality factor, higher the quality factor lower the Bandwidth.
Q = (1/R)*(sqrt(L/c));
fr = 1/(2*pi*sqrt(LC)); ---- resonant frequency.
so BW = R/(2*pi*L);
so on substituting the values BW = 31.8 Hz

Oneidensis said: (Jun 23, 2011)  
My answer is 200... iIve been solving this so many times.. here's the formulas I used,

f=1/(square roof of (LC))
then,
Q= (1/fRC) ; Q= (fL/R)
then,
B=f/Q... B=200

Sap said: (Aug 12, 2011)  
Hussain you are right.

Seenivasagan said: (Sep 1, 2011)  
Bandwidth(BW)=fr/Q
Q=(2*pi*fr*L)/R
fr=1/(2*pi*root LC)
by applying this ,
we can get fr=71.21
Q=2.236

BW=fr/Q
=71.21/2.236
=31.84
approximately 31.8

Sandeep said: (Sep 3, 2011)  
Q=Fr/BW;
BW=Fr/Q;
Fr=1/2*PI*ROOT(L*C);
Q=(1/R)(ROOT(L/C));

M.V.Krishna said: (Sep 6, 2011)  
BW=fr/Q;

fr=1/(2*pi*underroot(L*C));

Q=(1/R)*underroot(L/C);

BW=R/(2*pi*L);

=>1Kohm/(2*pi*5H);

=32.3Hz

Amrita said: (Sep 17, 2011)  
BANDWIDTH= Resonant freq/ Quality Factor

Resonant Frequency= 1/(2*pi*sqrt of(L*C))

Quality Factor= 1/R*(sqrt(L/C))


Using above fomula we can determine, Bandwidth=31.83 .

Fadi said: (Mar 27, 2012)  
B.W=FR/Q

Q=(1/R)SQRT(L/C)
FR=1/2*PI*SQRT(LC)

B.W=[1/2*PI*SQRT(LC)]/(1/R)SQRT(L/C)
B.W=R*SQRT C / 2*PI*L*SQRT C
B.W=R/2*PI*L

Sreeyush Sudhakaran said: (Aug 19, 2012)  
B.W=fr/Q

Q=(2*Pi*fr*L)/R

B.W = fr/((2*Pi*fr*L)/R) = R/2*Pi*L = 1000/2*3.14*5 = 31.8Hz

Alka said: (Jan 15, 2013)  
BW=fr/Q
Q=(2*pi*fr*L)/R
Bw=R/(2*pi*L)
=31.83

Manjunath said: (May 11, 2013)  
Bandwidth = R/2*pi*L . BW= 1/2*3.14*5 = 31.8 Hz.

Govind Singh Chouhan said: (Nov 25, 2013)  
Data Given:

R = 1k.
C = 1uF.
L = 5H.

So, resonance freq. is = 1/2*pi*sqrt(LC).

(fo is a resonance freq.)

fo = 1/2*3.14*sqrt(5*1*10^-6)).
fo = 1/2*3.14*sqrt(0.000005).
fo = 71.42Hz.

we know about the Quality factor "Q",

Q = WoL/R.
Q = 2*pi*fo*5/1k.
Q = 2.24.

The relationship between Q,fo and BW is:

Q = fo/BW.

So BW = fo/Q.

BW = 71.42/2.24.

BW = 31.88Hz.

Shah said: (Apr 5, 2014)  
B' = R/L in radians.
B' = 1000/5.
B' = 200.
B = B'/2*pi.
B = 200/2*pi.
B = 31.83.

Daks said: (Oct 16, 2014)  
Easy way.

BW = Fr/Q
BW = 1/2*pi*L/R
BW = R/2*pi*L
BW = 31.83

Ruben said: (Mar 27, 2015)  
So, when you decrease the resistance in the circuit Q will increase and bandwidth and will decrease, but phase angle theta will increase. The circuit efficiency will decrease number.

Dhana said: (Jun 4, 2015)  
XL=wL.
XL=(2*pi*f)(5H).
XL=2*22/7*5.
XL=31.42 app.

Krupal Gowda Jedrali said: (Jul 12, 2015)  
= r/2.pai.L formula.
= 1000/2*pai*5 = 31.8105 hz.

Gaurav Kumar Yadav said: (Aug 19, 2015)  
As Bandwidth = Resonant frequency/Quality Factor.

And Resonant Frequency = 1/(2*pi*Sqareroot LC).

And Quality factor = 1/R*squareroot(L/C).

Now BW = 1/ (2*pi*Suareroot LC)/1/R*squareroot (L/C) = R/(2*pi*L).

BW = 1000/(2*3.14*5) = 31.8 Hz.

Laurent P .Eranga said: (Nov 23, 2015)  
First find fr = 1/6.28 times square root of LC.

You will got 71.2 hz.

Then find xl = 6.28 times fl you will got 2.23 k if xl = xc.

Then q = xl/r you will got 2.23 k/1 k = 2.235.

If the formula for bw = fr/q.

fr = 71.2 and q = 2.235 so bw = fr/q will be equals to 31.8 hz.

Jatin Choudhary said: (Feb 21, 2016)  
f = R/2*3.14*L.

Ashish said: (May 31, 2017)  
Here, r/2 * π * L = 31.8.

Vijay said: (Sep 12, 2017)  
Q=(omega*L)/R.
BW=f/Q,
=> BW=(f*R)/(w*L)
=> BW=R/(2*pi*L)
=> Bw=31.8.

Mody Shaban said: (Dec 30, 2017)  
HOW?

Ayush Purwar said: (Jan 23, 2018)  
Bandwidth= R/(2*L)...Hz.
= 1000/(2*3.14*5).
= 31.84 Hz.

Suma said: (Sep 27, 2018)  
Here, R/(2*π*L) = 31.8.

Post your comments here:

Name *:

Email   : (optional)

» Your comments will be displayed only after manual approval.