Relation of I and V in secondry coil of transformer?

[waqarrashid33]

One of the function of transformer is to increase the Voltage and decrease the current,It is according to P=IV.The decrease in the current will produce the loss in energy from the resistance of supply lines i.e P=I^2.R.

My question is that the P=(V^2)/R is also the power loss and in case of increase in voltage it increases?
HOw is it possible the Voltage will be greater but current will be samall,is it the failure of Ohm,s Law?
What is in the 2nd relation that it disobey it,or what is the error in my concept?
Plz give a comprehensive and simple answer of intermediate level.

 

[Valerie Park]

No, increasing the voltage does not necessarily increase the power loss. This is because power is proportional to the square of the current, so if the current is decreased, then the power will decrease as well. In other words, the power loss from the supply lines is determined by both the voltage and the current, since power is equal to voltage multiplied by current (P=IV). So, if the voltage is increased while the current is decreased, then the overall power loss can stay the same or even decrease. This is why transformers are used to increase voltage levels - to reduce the amount of current required to transmit the same amount of power.This does not contradict Ohm's law (V=IR) - it simply means that the power loss is not strictly proportional to the voltage.