Physics-ch-28/exercise 2
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Question 2





Q2: Two-V batteries—with their positive terminals in the same direction—are inserted in series into a flashlight. One battery has an internal resistance of Ω, and the other has an internal resistance of Ω. When the switch is closed, the bulb carries a current of A.
(a) What is the bulb’s resistance?
(b) What fraction of the chemical energy transformed appears as internal energy in the batteries?