# Electrical Engineering - Transformers - Discussion

### Discussion :: Transformers - General Questions (Q.No.16)

16.

A certain amplifier has 600 internal resistance looking from its output. In order to provide maximum power to a 4 speaker, what turns ratio must be used in the coupling transformer?

 [A]. 8 [B]. 0.8 [C]. 0.08 [D]. 80

Explanation:

No answer description available for this question.

 Shaijuts said: (Jan 9, 2011) Pow((Ns/Np),2) = Zs/Zp ie. pow(k,2) = 4/600 k=sqrt(4/600) k=0.08

 Saritha said: (Aug 24, 2011) Here, Load resistance(destination)=4 ohms Source resistance=600 ohms k=(r2/r1)^0.5 =(4/600)^0.5 =0.0816 k=0.0816 ohms

 Siri said: (May 24, 2012) @Saritha. Transformation ratio is unit less quantity. Not measured in ohms.

 Manish said: (Jun 21, 2012) V2/I2 = 4. V1/I1 = 600. V2xI1/V1xI2 = 4/600. N2 = 4/600N1 = 0.08.

 Akash.Bhure said: (Apr 30, 2014) Internal resistance(R1)=600 ohms. Output speaker(R2)=4 ohms. R1 = R2/K^2. 600 = 4/K^2. K^2 = 4/600 = 0.0066. K = sqrt(0.0066) = 0.081.

 Love said: (Oct 10, 2014) But it is asked to determine turn ratio = 1/K.

 Ashim said: (Jan 3, 2015) Turns ratio K = N2/N1= sqrt (R2/R1) = sqrt (4/600) = 0.08.

 E.Sravani said: (Apr 1, 2015) Power = i^2r. Input power = i1^2r1 = i1^2(600). Output power = i2^2r2 = i2^2(4). P(in) = P(out). i1^2(600) = i2^2(4). K^2 = (4/600) {(i1/i2)^2 = k^2}. K = 0.08.

 Rakesh Alliwar said: (Jul 3, 2016) Yes, 0.08 is the correct answer.

 Rajesh said: (Jul 31, 2016) Transformer transfer constant power. V1 * I1 = V2 * I2. V1 * V1/r1 = V2 * V2/ r2. V1 ^2 / r1 = V2 ^2 / r2. Sq of (V2/V1) = r2 / r1. (V2 / V1) = sq rt of (r2 / r1). k = sq rt of (4 / 600). k = 0.081.

 Sahal said: (Aug 16, 2016) How can we solve the sqrt without a calculator? any one please suggest me.

 Mohsin Yaqoob said: (Sep 29, 2016) Simple! Turn ratio = sqr (load impedance/source impedance). Here load imp is speaker ie, 4ohm and source is 600ohm. so, sqr (4/600) = 0.08.

 Ajit said: (Nov 22, 2016) According to me, it's the wrong answer. The turns ratio = (source impedence/load impedence)^0.5. Answer = 12.24.

 Din said: (Feb 1, 2017) As per my knowledge. Turns ratio = Np/Ns not Ns/Np. Is/Ip is the turns ratio. So, I think it is the wrong answers.

 Mouneshwara said: (Feb 4, 2017) @Din. Turns ratio ns/np is the correct one.

 Amani Naidu said: (Feb 16, 2017) No, turns ratio is n1/n2. Transformation ratio is n2/n1. You are right @Din.

 Er Mahesh said: (Apr 12, 2017) Thanks a lot @RAJESH & @Sravani.

 Suhail said: (Sep 1, 2017) Here, K^2=Z1÷Z2.

 Nishant said: (Oct 8, 2018) I think it is the wrong answers. Because, turn ratio of the transformer is V1/V2, N1/N2, E1/E2, and I2/I1. So, transformer transfer constant power. V1 * I1 = V2 * I2. V1 * V1/R1 = V2 * V2/ R2. V1 ^2 / R1 = V2 ^2 / R2. V1^2/V2^2 = R1/R2, V1/V2 = Sq. Rt. Of (R1/R2). We know that T.R:-K = V1/V2 So, K = 600/4 =12.24.