In a 6-volt storage battery with an internal resistance of 0.01 ohm, a 6-volt, 3-watt lamp is connected. What current flows through the circuit?

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Multiple Choice

In a 6-volt storage battery with an internal resistance of 0.01 ohm, a 6-volt, 3-watt lamp is connected. What current flows through the circuit?

When a device is rated at a certain voltage and power, its resistance can be found from R = V^2 / P. Here the lamp has R = 6^2 / 3 = 12 ohms. The battery adds its own internal resistance of 0.01 ohms, so the total circuit resistance is 12.01 ohms. With a 6-volt source, the current is I = V / R_total = 6 / 12.01 ≈ 0.4996 A, which matches the given option (about 0.4995 A). The small internal resistance lowers the current slightly from the ideal 0.5 A.

When a device is rated at a certain voltage and power, its resistance can be found from R = V^2 / P. Here the lamp has R = 6^2 / 3 = 12 ohms. The battery adds its own internal resistance of 0.01 ohms, so the total circuit resistance is 12.01 ohms. With a 6-volt source, the current is I = V / R_total = 6 / 12.01 ≈ 0.4996 A, which matches the given option (about 0.4995 A). The small internal resistance lowers the current slightly from the ideal 0.5 A.

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