In a circuit with 220 volts and 55 ohms of resistance, how much total resistance is needed to limit the current to 2 amperes?

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Multiple Choice

In a circuit with 220 volts and 55 ohms of resistance, how much total resistance is needed to limit the current to 2 amperes?

Explanation:
To determine the total resistance needed in the circuit to limit the current to 2 amperes while maintaining the supplied voltage of 220 volts, we can begin by applying Ohm's Law. Ohm's Law states that the current (I) flowing through a conductor between two points is directly proportional to the voltage (V) across the two points and inversely proportional to the resistance (R) of the conductor. This relationship can be expressed with the formula: \[ V = I \times R \] To find the total resistance required, we can rearrange the formula to solve for R: \[ R = \frac{V}{I} \] Substituting in the values from the question: - V = 220 volts - I = 2 amperes \[ R = \frac{220 \text{ volts}}{2 \text{ amperes}} = 110 \text{ ohms} \] This calculation shows that a total resistance of 110 ohms is needed to achieve the desired current of 2 amperes with the provided voltage. If there is already 55 ohms of resistance in the circuit, then to find any additional resistance required, we must subtract the existing resistance from the total resistance needed

To determine the total resistance needed in the circuit to limit the current to 2 amperes while maintaining the supplied voltage of 220 volts, we can begin by applying Ohm's Law. Ohm's Law states that the current (I) flowing through a conductor between two points is directly proportional to the voltage (V) across the two points and inversely proportional to the resistance (R) of the conductor. This relationship can be expressed with the formula:

[ V = I \times R ]

To find the total resistance required, we can rearrange the formula to solve for R:

[ R = \frac{V}{I} ]

Substituting in the values from the question:

  • V = 220 volts

  • I = 2 amperes

[ R = \frac{220 \text{ volts}}{2 \text{ amperes}} = 110 \text{ ohms} ]

This calculation shows that a total resistance of 110 ohms is needed to achieve the desired current of 2 amperes with the provided voltage.

If there is already 55 ohms of resistance in the circuit, then to find any additional resistance required, we must subtract the existing resistance from the total resistance needed

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