Step-Up Transformer Conceptual Problem

AI Thread Summary
In an ideal transformer, when the voltage is stepped up, the current must decrease to conserve energy, as power remains constant. The relationship between primary and secondary voltage and current is given by the equation Ep/Np = Es/Ns. Since power is the product of voltage and current, an increase in voltage results in a proportional decrease in current. Therefore, the correct answer to what must be decreased is current. Understanding this principle is crucial for solving transformer-related problems.
longcatislong
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Homework Statement



Even for an ideal transformer, we can't get "something for nothing". If this transformer steps up the voltage, what must be decreased?
a) power
b) current
c) resistance

The Attempt at a Solution



Ep/Np=Es/Ns

I believe it's power or current, but these two are related. So I'm not sure which one to choose.
 
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longcatislong said:

Homework Statement



Even for an ideal transformer, we can't get "something for nothing". If this transformer steps up the voltage, what must be decreased?
a) power
b) current
c) resistance

The Attempt at a Solution



Ep/Np=Es/Ns

I believe it's power or current, but these two are related. So I'm not sure which one to choose.

An ideal transformer has no losses. What is your answer now?
 

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