Circuit A has a resistance of 7.5 ohms, and circuit B has a resistance of 5 ohms. Which statement about the circuits must be correct?(1 point)

Responses

If the voltage of circuit A is equal to the voltage of circuit B, then the current in circuit A is equal to the current in circuit B.
If the voltage of circuit A is equal to the voltage of circuit B, then the current in circuit A is equal to the current in circuit B.

If the current in circuit A is equal to the current in circuit B, then the voltage in circuit A is less than the voltage in circuit B.
If the current in circuit A is equal to the current in circuit B, then the voltage in circuit A is less than the voltage in circuit B.

If the voltage of circuit A is equal to the voltage of circuit B, then the current in circuit A is less than the current in circuit B.
If the voltage of circuit A is equal to the voltage of circuit B, then the current in circuit A is less than the current in circuit B.

If the current in circuit A is less than the current in circuit B, then the voltage in circuit A is less than the voltage in circuit B.

1 answer

To analyze the given statements, we can use Ohm's Law, which states:

\[ V = I \cdot R \]

Where:

  • \( V \) is the voltage,
  • \( I \) is the current, and
  • \( R \) is the resistance.

Given:

  • Resistance of circuit A, \( R_A = 7.5 , \Omega \)
  • Resistance of circuit B, \( R_B = 5 , \Omega \)
  1. If the voltage of circuit A is equal to the voltage of circuit B, then the current in circuit A is equal to the current in circuit B.

    • This is false, because for the same voltage, the currents will be different due to different resistances (Ohm's Law \( I = \frac{V}{R} \)).
  2. If the current in circuit A is equal to the current in circuit B, then the voltage in circuit A is less than the voltage in circuit B.

    • This is also false. If the currents are equal, we can find the voltages using Ohm's Law, and since \( R_A > R_B \), \( V_A \) would actually be greater than \( V_B \).
  3. If the voltage of circuit A is equal to the voltage of circuit B, then the current in circuit A is less than the current in circuit B.

    • This statement is true. Given \( V_A = V_B \), since \( R_A > R_B \), we have \( I_A = \frac{V_A}{R_A} \) and \( I_B = \frac{V_B}{R_B} \). Since \( R_A > R_B \), it follows that \( I_A < I_B \).
  4. If the current in circuit A is less than the current in circuit B, then the voltage in circuit A is less than the voltage in circuit B.

    • This is false. The current could be less in circuit A even if the voltage is the same, due to higher resistance.

Based on this analysis, the correct statement is:

If the voltage of circuit A is equal to the voltage of circuit B, then the current in circuit A is less than the current in circuit B.