If power dissipated in the 9 Ω resistor in the circuit shown is 36 Watt, the potential difference across the 2 Ω resistor is 

If power dissipated in the 9 Ω resistor in the circuit shown is 36 Watt, the potential difference across the 2 Ω resistor is  Correct Answer 10 Volt

CONCEPT:

• If a current I flows through a given element in your circuit, losing voltage V in the process, the power dissipated (P) by that circuit dissipated by that current element is the product of that current and voltage.

P = V × I = I² R

• The potential difference (V): The amount of current multiplied by the resistance. one volt is equal to one joule of energy being used by one coulomb of charge when it flows between the two points in a point

V = I R

CALCULATION:

• Current  flows through the 9 Ω  resistor  is 

I₁² = 36/9 = 4

I₁ = 2 A

• As the resistors 9 Ω and 6Ω  are connected in parallel, therefore potential difference across them is the same.

∴ 9 I₁ = 6 I₂ ; I₂ = (9 × 2)/6 = 3A

current drawn from the battery is 

I = I₁ + I₂ = (2 +3) A = 5A

The potential difference across the 2 Ω resistor is = (5 A) (2 Ω ) = 10 V. 

Hence option 4 is correct.