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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?

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 less than 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

User Marcanuy
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3.4k points

1 Answer

7 votes

Answer:

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

Step-by-step explanation:

To know the the correct answer to the question, do the following:

Case 1: Let the circuit A and B have equal voltage say 24 V.

For Circuit A:

Voltage (V) = 24 V

Resistance (R) = 7.5 ohms

Current (I) =?

V = IR

24 = I × 7.5

Divide both side by 7.5

I = 24 / 7.5

I = 3.2 A

For Circuit B:

Voltage (V) = 24 V

Resistance (R) = 5 ohms

Current (I) =?

V = IR

24 = I × 5

Divide both side by 5

I = 24 / 5

I = 4.8 A

Thus for the same voltage, current in circuit A is less than the current in B.

Case 2: Let circuit A and B have equal current say 2 A

For circuit A:

Current (I) = 2 A

Resistance (R) = 7.5 ohms

Voltage (V) =?

V = IR

V = 2 × 7.5

V = 15 V

For Circuit B:

Current (I) = 2 A

Resistance (R) = 5 ohms

Voltage (V) =?

V = IR

V = 2 × 5

V = 10 V

Thus, for the same current, the voltage in circuit A is greater than the voltage in B

Case 3: Let circuit A have a current of 4 A and circuit B have a current of 5 A

For circuit A:

Current (I) = 4 A

Resistance (R) = 7.5 ohms

Voltage (V) =?

V = IR

V = 4 × 7.5

V = 30 V

For circuit B:

Current (I) = 5 A

Resistance (R) = 5 ohms

Voltage (V) =?

V = IR

V = 5 × 5

V = 25 V

Thus, when the current in circuit A is less than the current in circuit B, the voltage in circuit A is greater than the voltage in circuit B.

From the illustrations above and the options given in the question, the current answer 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

User Mousomer
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3.5k points