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4 votes
4 votes
Please help!! :)

For this circuit, what will be the voltage drop across R1?

A. 21.3 V

B. 14.2 V

C. 45.0 V

D. 9.47 V

Please help!! :) For this circuit, what will be the voltage drop across R1? A. 21.3 V-example-1
User Afjalur Rahman Rana
by
2.9k points

2 Answers

6 votes
6 votes

Answer:

9.47

Step-by-step explanation:

Just Took the Test

User Nirav Kotecha
by
2.9k points
26 votes
26 votes

Answer:

Option D. 9.47 V

Step-by-step explanation:

We'll begin by calculating the equivalent resistance of the circuit. This can be obtained as follow:

Resistor 1 (R₁) = 20 Ω

Resistor 2 (R₂) = 30 Ω

Resistor 3 (R₃) = 45 Ω

Equivalent Resistance (R) =?

R = R₁ + R₂ + R₃ (series connections)

R = 20 + 30 + 45

R = 95 Ω

Next, we shall determine the current in the circuit. This can be obtained as follow:

Voltage (V) = 45 V

Equivalent Resistance (R) = 95 Ω

Current (I) =?

V = IR

45 = I × 95

Divide both side by 95

I = 45 / 95

I = 0.4737 A

Finally, we shall determine, the voltage across R₁. This can be obtained as follow:

NOTE: Since the resistors are in series connection, the same current will pass through them.

Current (I) = 0.4737 A

Resistor 1 (R₁) = 20 Ω

Voltage 1 (V₁) =?

V₁ = IR₁

V₁ = 0.4737 × 20

V₁ = 9.47 V

Therefore, the voltage across R₁ is 9.47 V.

User Timothy Schoonover
by
3.0k points