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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?

User Jamieb
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1 Answer

2 votes

Answer:

Step-by-step explanation:

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


P=(V^2)/(R) and


P=I^2\cdot R

where
V=Potential\ difference


R=resistor


I=current

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
P=(V^2)/(R) 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
P=I^2R

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

User Renato Borges
by
8.8k points
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