Question

In the circuit shown power dissipated in 12 ohm resistance is 6 watt. What is the power dissipated in the 8 ohm resistance ?
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Answer 1

Given :

Power dissipated in 12Ω resistance = 6 watt

To find :

Power dissipated in 8Ω resistance = ?

Solution :

• As shown in the figure both the resistances are connected in parallel to the battery . So the potential difference across the terminals of both the resistances would be same

• The power dissipiated by the resistor is given by the formula

                   $P=\frac{V^{2} }{R}$

                   $6=\frac{V^{2} }{12} \rightarrow Equation(1)$

                   $P=\frac{V^{2} }{8} \rightarrow Equation(2)$

• By diving equations 1 & 2 we get, P = 9 watt

  The power dissipated in 8Ω resistance is 9 watt

                   

Answer 2

Answer:

6=v^2/r

6=v^2/12

v=root 1/2

p=vsquare / r

p=root 1/2 square / 8

p=4 watt