Power Calculation for Three Resistors in a Circuit

In summary, the conversation discusses the calculation of power dissipation across three resistors connected to a battery. Using the given values of voltage and resistance, the equivalent resistance of the circuit is found to be 102 ohms. However, when calculating the power for each resistor, the resulting values do not match the expected answer. Further clarification on the given values is needed to determine the correct solution.
  • #1
shortman12012
13
0

Homework Statement




Three resistors are connected across a battery as shown in the figure. (Let V = 141 V and R1 = R2 = R3 = 204 Ω.)

http://www.webassign.net/bauerphys1/25-p-057-alt.gif

(a) How much power is dissipated across the three resistors?
P1 =
P2 =
P3 =


Homework Equations



P=IV

The Attempt at a Solution



I solved for each of the voltages across each resistor. Each resistor is 68 ohms.
so the equivalent resistance of the circuit is 102 = 68 + 1/[2(1/68)]
Using that and the voltage 141 I get the current I = 1.38235 A
Using that I solve for V1 = 94 V and V2 and V3 = 46.999 V

So to get the power for R1 I would take the voltage 94 and multiply it by the current 1.38235 and get 129.9409 W but the answer is incorrect so I'm not sure what I'm doing wrong. The same goes for P2 and P3 when I do the same thing
 
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  • #2
I don't know, your original statement said the resistance was 204, do you have the right values?
 

What is power in a circuit?

Power in a circuit is the rate at which energy is transferred or consumed. It is measured in watts (W) and is calculated by multiplying the voltage (V) by the current (I).

How do you calculate power in a circuit?

To calculate power in a circuit, use the equation P = VI, where P is power in watts, V is voltage in volts, and I is current in amps.

What is the difference between AC and DC power?

AC (alternating current) power is the type of power that is commonly used in homes and businesses. It flows in both directions, constantly reversing its polarity. DC (direct current) power, on the other hand, flows in only one direction and is commonly used in electronics and batteries.

What is the unit of measurement for power in circuits?

The unit of measurement for power in circuits is watts (W). However, kilowatts (kW) and megawatts (MW) are also commonly used for larger power systems.

How can power be increased in a circuit?

Power in a circuit can be increased by increasing either the voltage (V) or the current (I). This can be done by using a higher voltage power source or by adding more components to the circuit to increase the flow of current.

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