In this circuit, two batteries, one with a potential difference of 10 V and the other with a potential difference of 20 V, are connected in series across a resistance of 90$\Omega$. The current in the circuit is
A) 3.0 A
B) 0.33 A
C) 9.0 A
D) 30 A
E) 4.5

Question

In this circuit, two batteries, one with a potential difference of 10 V and the other with a potential difference of 20 V, are connected in series across a resistance of 90$\Omega$. The current in the circuit is
A) 3.0 A 
B) 0.33 A 
C) 9.0 A 
D) 30 A 
E) 4.5

Quizplus · Accepted Answer

When batteries are connected in series, the total potential difference is the sum of the individual potential differences. Therefore, the total potential difference in this circuit is 10 V + 20 V = 30 V. Using Ohm's Law (V = IR) and the given resistance of 90 ohms, we can solve for the current in the circuit: I = V/R = 30 V/90 ohms = 0.33 A. Therefore, the correct answer is B.

In This Circuit, Two Batteries, One with a Potential Difference Ω\OmegaΩ

In This Circuit, Two Batteries, One with a Potential Difference $\Omega$