How Does a Model Train Transformer Work?

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The model train transformer operates by converting 120-V AC input to a lower output voltage for the train. The calculations show that the voltage across the tracks is 5.6V, derived from the current and voltage relationship. It is identified as a step-down transformer since the secondary voltage is lower than the primary voltage. A correction was noted in the calculations regarding the current value used. The discussion confirms the understanding of transformer functionality and voltage conversion.
jena
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Hi,

My Question:

A model train transformer plugs into 120-V ac and draws 0.35A while supplying 7.5A to the train. (a)What voltage is present across the tracks? (b) is the transformer step-up or step down?

Work

Part A:

I'V'=I"V"
(0.25A)(120V)=(7.5A)(V")
((0.25A)(120V))/(7.5A)=V"
V"=5.6V

Part B:

Step-down, because the secondary voltage is lower than the primary voltage.

Is it correct:confused:

Thank You:smile:
 
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You are correct. (Note typo in your part A equations: you wrote "0.25A" instead of "0.35A".)
 
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