How Do You Calculate Resistance, Current, and Power in Parallel Circuits?

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The discussion focuses on calculating resistance, current, and power in a parallel circuit with ten 110-ohm lamps connected to a 110-V line. The total resistance is calculated using the formula for parallel resistors, resulting in 11 ohms. The current flowing through the line is determined using Ohm's law, yielding 10 amps. Power supplied to the circuit is calculated as 110 volts multiplied by 10 amps, equaling 1100 watts. The calculations and methodology presented are confirmed to be correct.
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1. Ten 110-ohm lamps are connected in parallel to a 110-V house line. A) What is the combined resistance of the ten lamps? B) What current flows in the line when all ten lamps are operating? C) What power is then being supplied to the circuit by the line?

I just wanted to have someone check my work and see if I attacked this problem the right way.




2. 1 / Rt = 1 / r1 + 1 / r2... (total resistance for resistors in parallel)
V = IR
P = VI




3. A) This is simple: add (1/110) ten times, giving (1/11).. Then cross multiplication can be used to find that Total resistance is equal to 11 ohms

B) To find the current that flows in the line, we can use ohms law and substitute 110 volts = 11 ohms * I, and I will evaluate to 10 amps

C) P = (110 volts)(10 amps) = 1100 right?
 
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The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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