1. A battery whose emf is 6.0 V is connected to a 2.0 Ω resistor. The voltage drop across the 2.0 Ω resistor is 5.0 V. What is its internal resistance? a) 0.40 Ω b) 1.7 Ω c) 2.4 Ω d) 2.5 Ω 2. Relevant equations VT=ε-Ir 3. The attempt at a solution I know that ε=6.0 V VT=5.0 V and a resistor= 2.0 Ω The resistor part is what I don't understand. If I'm looking for the internal resistance, I'm looking for the resistance of the resistor. So if they give me the resistance to be 2.0 Ω in the question, shouldn't the answer be 2.0? The answer is a) 0.40 Ω.