What is the Voltage of Bulb D in the Circuit?

AI Thread Summary
The discussion centers on calculating the voltage of bulb D in a circuit with a total voltage supply of 4 watts and identical bulbs with a resistance of 3 ohms. The effective resistance of bulbs A, B, and C is determined to be 2 ohms, leading to a total circuit resistance of 5 ohms. The current is calculated as 4/5 A, resulting in a voltage for bulb D of 12/5 W. However, a significant error is noted in the problem statement, as the supplied voltage should be in volts, not watts, since watts measure power, not voltage. Clarifying this terminology is essential for accurate calculations.
Max T
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Homework Statement


What is the voltage of the bulb D? Given the total voltage supplied by the cells is 4 watts and each bulb is identical and has a resistance of 3 ohms

Homework Equations


V=IR

The Attempt at a Solution


By assuming bulb A,B, and C as a group , their effective resistance would be 2 ohms.
Thus, the effective resistance of the circuit is Effective resistance of bulb A,B,C + resistance of Bulb D = 5 ohms
Hence, the current across the circuit is total voltage supplied / effective resistance of the whole circuit = 4/5 A. Therefore, the voltage of bulb D is 4/5A x 3 ohms = 12/5 W

*forgive me for my random attempt , since my teacher never taught me anything about this part
 

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Max T said:

Homework Statement


What is the voltage of the bulb D? Given the total voltage supplied by the cells is 4 watts and each bulb is identical and has a resistance of 3 ohms

Homework Equations


V=IR

The Attempt at a Solution


By assuming bulb A,B, and C as a group , their effective resistance would be 2 ohms.
Thus, the effective resistance of the circuit is Effective resistance of bulb A,B,C + resistance of Bulb D = 5 ohms
Hence, the current across the circuit is total voltage supplied / effective resistance of the whole circuit = 4/5 A. Therefore, the voltage of bulb D is 4/5A x 3 ohms = 12/5 W

*forgive me for my random attempt , since my teacher never taught me anything about this part
The units given in the statement of your problem don't make sense.

What is the problem, word for word, as it was given to you?
 
Max T said:
What is the voltage of the bulb D? Given the total voltage supplied by the cells is 4 watts and each bulb is identical and has a resistance of 3 ohms
There is an error here. I think you mean the voltage supplied by the cells is 4 volts

voltage is a measure of the EMF (electromotive force)
w is for watts and it is a measure of energy over time (power) 1 watt = 1 joule for 1 second
 
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