Question

select the best answer for the question. 14. a complete circuit contains two parallel - connected devices and a generator for providing the electromotive force. the resistance of the first device is 12 ohms, the resistance of the second device is 4 ohms, and the voltage developed by the generator is 40 v. whats the magnitude of the current flowing through the first device?
a. 10 a
b. 3.33 a
c. 8 a
d. 13.32 a
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Explanation:

Step1: Recall Ohm's Law and parallel circuit property

In a parallel circuit, the voltage across each device is equal to the voltage of the generator. Ohm's Law is \( I = \frac{V}{R} \), where \( I \) is current, \( V \) is voltage, and \( R \) is resistance.

Step2: Identify values for first device

For the first device, \( V = 40 \, \text{V} \) (since parallel, voltage is same as generator) and \( R = 12 \, \Omega \).

Step3: Calculate current through first device

Using \( I = \frac{V}{R} \), substitute \( V = 40 \) and \( R = 12 \):
\( I = \frac{40}{12} \approx 3.33 \, \text{A} \)

Answer:

B. 3.33 A