The power dissipated in a resistor is given by p = v 2 / r , which means power decreases if resistance increases. yet this power is also given by p = i 2r , which means power increases if resistance increases. explain why there is no contradiction here?

Explanation:

Power Dissipated in a resistor is given by two methods i.e.

 and

where

both formula gives Power but Former is used when voltage is constant i.e. when resistors are in parallel and the later is used when the resistor are in series .

Though can also be used in series but we have to calculate the Potential drop across each resistor then we can apply the formula.

Similar is with

First we have to calculate current through each resistor then we can apply the Formula

explanation:

v=uf/(u-f)

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