Answer:
Option B. 10 V.
Step-by-step explanation:
The following data were obtained from the question:
Resistor 1 (R₁) = 20 Ω
Resistor 2 (R₂) = 40 Ω
Resistor 3 (R₃) = 60 Ω
Potential difference (V) = 60 V
Next, we shall determine the total resistance of the circuit.
The circuit is in series connection. Therefore the total resistance (R) can be obtained by adding up R₁, R₂ and R₃ together as shown below:
R = R₁ + R₂ + R₃
R = 20 + 40 + 60
R = 120 Ω
Therefore, the total resistance in the circuit is 120 Ω
Next, we shall determine the current flowing in the circuit.
Note: The same current will flow through each resistor since they are in series connection.
The current flowing in the circuit can be obtained as follow:
Potential difference (V) = 60 V
Total resistance (R) = 120 Ω
Current (I) =..?
V = IR
60 = I x 120
Divide both side by 120
I = 60/120
I = 0.5 A
Therefore, the current flowing in the circuit is 0.5 A
Now, we can calculate the potential drop across R₁ as follow:
Resistor 1 (R₁) = 20 Ω
Current (I) = 0.5 A
Potential difference cross R₁ (V₁) =.?
V₁ = IR₁
V₁ = 0.5 x 20
V₁ = 10 V
Therefore, the potential difference across R₁ is 10 V.