Transformers and Power Transmission Question

[predentalgirl1]

Please Help me to see if I've worked this correctly. Thanks!

The primary coil of an ideal transformer has 720 turns, and the secondary coil has 180 turns. If the primary coil carries 15 A at a voltage of 120 V, what are (a) the voltage and (b) the output current of the secondary coil?









Given that,
Np = 720
Ns = 180
I p = 15 A
Is =?
Ep = 120 V
Es =?

i have,
Ep/Es = Is/Ip = Np/Ns


Therefore,
Out put current Is = I p x Np/Ns

= 15 x 720/180

= 60 A

Voltage = Ep x Ip/Is

= 120 x 15/60

= 30 V

 

[anathema]

Your calculations are correct. Good job! It's important to remember that in an ideal transformer, the power remains the same on both sides. This is why we can use the equation Ep/Es = Ip/Is to find the output current and voltage. Keep up the good work!

 

[Moetasim]

Your calculations look correct. In an ideal transformer, the voltage and current are inversely proportional to the number of turns in the coils. So, in this case, since the secondary coil has 1/4th the number of turns as the primary coil, the voltage will be 1/4th and the current will be 4 times that of the primary coil. Your calculations reflect this relationship. Good job!