What is the magnitude of the potential difference across the 20-$\Omega$ resistor?
A)3.2 V
B)7.8 V
C)11 V
D)5.0 V
E)8.6 V

Question

What is the magnitude of the potential difference across the 20-$\Omega$ resistor? 
A)3.2 V 
B)7.8 V 
C)11 V 
D)5.0 V 
E)8.6 V

Quizplus · Accepted Answer

Using Kirchhoff's loop rule, we can write:
-12 V + 16 I - 20 I = 0
Solving for I, we get:
I = 0.3 A
The potential difference across the 20-ohm resistor can be found using Ohm's law:
V = IR = (0.3 A)(20 ohm) = 6 V
Therefore, the magnitude of the potential difference across the 20-ohm resistor is 6 V, but since the question asks for the absolute value, the answer is 6 V. However, none of the answer choices match 6 V, so we choose the closest option, which is B) 7.8 V.

What Is the Magnitude of the Potential Difference Across the 20-