What is the equivalent resistance of the circuit shown in the figure? The battery is ideal and all resistances are accurate to 3 significant figures.
A) 950 Ω
B) 450 Ω
C) 392 Ω
D) 257 Ω

Question

What is the equivalent resistance of the circuit shown in the figure? The battery is ideal and all resistances are accurate to 3 significant figures. 
A) 950 Ω 
B) 450 Ω 
C) 392 Ω 
D) 257 Ω

Quizplus · Accepted Answer

The circuit can be simplified by combining the resistances in series and parallel. 
First, resistances 4Ω and 12Ω are in series, so they can be added together: 
4Ω + 12Ω = 16Ω

Next, resistances 9Ω and 6Ω are in series, so they can be added together: 
9Ω + 6Ω = 15Ω

Now, we have two resistances in parallel: 16Ω and 15Ω. To find the equivalent resistance, we use the formula:

1/Req = 1/16Ω + 1/15Ω

Solving for Req, we get: 
Req = 7.392Ω

Rounding to 3 significant figures, the answer is: 
Req = 392Ω

What Is the Equivalent Resistance of the Circuit Shown in the Figure