Calculate Battery Energy Delivery Rate for Parallel Circuit

AI Thread Summary
The discussion focuses on calculating the energy delivery rate of a battery in a parallel circuit with three resistors: 15 ohms, 12 ohms, and 9 ohms. A current of 2 A flows through the 9-ohm resistor, prompting the need to find the equivalent resistance and applied voltage across the circuit. The equivalent resistance was calculated to be approximately 3.83 ohms using the formula for parallel resistors. The voltage across each resistor is the same, leading to the use of the equation V = I9 * r3 to find the applied voltage. The energy dissipation is determined using the formula W = V^2/r, highlighting the importance of using the correct equations in circuit analysis.
Ruleski
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Homework Statement



A current I9 = 2 A flows through the 9 ohm resistor. At what rate does the battery deliver energy to the entire circuit?

Homework Equations


There are 3 resistors in the circuit, all wired in parallel. r1=15 ohms, r2=12 ohms, r3=9 ohms


The Attempt at a Solution

 
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What is the expression for the equivalent resistance of the parallel combination?

What is the energy dissipation in the resistance?

In the problem I9 and r3 is given. Find the applied voltage across the parallel combination.
 
All I know is that resistance is 1/total=1/r1+1/r2+1/r3. I calculated 3.83 ohms
 
Ruleski said:
All I know is that resistance is 1/total=1/r1+1/r2+1/r3. I calculated 3.83 ohms

In parallel combination voltage across each branch of the resistance is the same.

So V = I9*r3.

Energy dissipation is W = V^2/r.
 
Thank You. I was using the wrong equation for the last step
 
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