Characteristics of Series Circuits

What is the total resistance in a series circuit?

• The sum of the individual resistances

• The product of the individual resistances

• The difference between the largest and smallest resistance

• The average of the individual resistances

Answer explanation

In a series circuit, the total resistance is calculated by adding the individual resistances together. This means the correct answer is 'The sum of the individual resistances', as resistances in series simply add up.

In the given circuit, what is the value of R1?

• 50Ω

• 75Ω

• 100Ω

• 225Ω

Answer explanation

R1 is determined by the circuit configuration. Given the options, 50Ω is the only value that satisfies the circuit's requirements, making it the correct choice.

What is the formula for calculating total resistance (RT) in a series circuit?

• RT = R1 + R2 + R3

• RT = R1 * R2 * R3

• RT = (R1 + R2 + R3) / 3

• RT = R1 - R2 - R3

Answer explanation

In a series circuit, the total resistance (RT) is the sum of all individual resistances. Therefore, the correct formula is RT = R1 + R2 + R3, which adds up the resistances in the circuit.

If R2 in the circuit is 75Ω, what is the value of R3?

• 100Ω

• 50Ω

• 75Ω

• 225Ω

Answer explanation

In a circuit, if R2 is 75Ω and we need to find R3, we can use the formula for resistors in series or parallel. Assuming a series configuration, R3 must be 100Ω to maintain the total resistance. Thus, the correct answer is 100Ω.

What is the total resistance if R1 = 50Ω, R2 = 75Ω, and R3 = 100Ω?

• 225Ω

• 150Ω

• 100Ω

• 50Ω

Answer explanation

To find the total resistance in series, simply add the resistances: R1 + R2 + R3 = 50Ω + 75Ω + 100Ω = 225Ω. Therefore, the total resistance is 225Ω.

If the total resistance is 225Ω, what is the sum of R1, R2, and R3?

• 225Ω

• 150Ω

• 100Ω

• 50Ω

Answer explanation

The total resistance of 225Ω indicates that R1, R2, and R3, when combined, equal this value. Therefore, the sum of R1, R2, and R3 is 225Ω, making it the correct choice.

In a series circuit, if R1 = 50Ω and R2 = 75Ω, what is the total resistance if R3 is 100Ω?

• 225Ω

• 150Ω

• 100Ω

• 50Ω

Answer explanation

In a series circuit, total resistance is the sum of all resistances. Here, R1 + R2 + R3 = 50Ω + 75Ω + 100Ω = 225Ω. Therefore, the total resistance is 225Ω.

Which of the following is true for resistors in series?

• The total resistance is less than the smallest resistor

• The total resistance is equal to the largest resistor

• The total resistance is the sum of all resistors

• The total resistance is the product of all resistors

Answer explanation

In a series circuit, the total resistance is calculated by adding the resistance values of each resistor. Therefore, the correct statement is that the total resistance is the sum of all resistors.

What is the resistance of R2 in the circuit?

• 20Ω

• 40Ω

• 60Ω

• 80Ω

Answer explanation

To find the resistance of R2, we can use Ohm's law or analyze the circuit configuration. Given the values, R2 is calculated to be 40Ω, which matches the correct answer choice.

What is the total resistance if R1 = 2Ω, R2 = 4Ω, and R3 = 8Ω, and R4 is not present?

• 1.14Ω

• 0.875Ω

• 2.5Ω

• 3Ω

Answer explanation

To find the total resistance of R1, R2, and R3 in parallel, use the formula 1/R_total = 1/R1 + 1/R2 + 1/R3. Substituting the values gives 1/R_total = 1/2 + 1/4 + 1/8 = 1.14Ω.