Effective resistance of secondary circuit in transformers

AI Thread Summary
To reduce a primary voltage of 150 V to a secondary voltage of 25 V, the transformer requires 22 windings in the secondary circuit. The effective resistance of the secondary circuit is calculated using the formula Reff = R(N1/N2)^2, where R is the load resistance. Despite using this equation, there is confusion regarding the calculation, as the expected effective resistance is not matching the derived value of 1500. The discussion highlights the importance of correctly applying the transformer equations and understanding that secondary circuit resistance depends solely on the load. Clarification on the calculations and formulas used is needed to resolve the discrepancy in the effective resistance.
sarah68
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Homework Statement


You need a transformer to reduce a voltage of 150 V in the primary circuit to 25 V in the secondary circuit. The primary circuit has 130 windings and the secondary circuit is completed through a 55 ? resistor. (a) How many windings should the secondary circuit contain? (b) What is the effective resistance of the secondary circuit?

Homework Equations



V2/V1=N2/N1

Reff= R(N1/N2)^2

The Attempt at a Solution



I solved part A. N2 is 22 windings. However, part B is 1500 but I can't seem to get that answer! I used the above equation but it doesn't give me that answer. Is the Reff equation that I'm using wrong? Please help me!
 
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i think you got the secondary circuit voltage and windings also. you its correct secondary circuit resistance is depend on load only.
 
Yes, but if I plug in the values with that equation I don't get 1500 for part B. I don't know what I'm doing wrong.
 

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