Two 1.50-v batteries—with their positive terminals in the same direction—are inserted in series into the barrel of a flashlight. one battery has an internal resistance of 0.320 ω, the other an internal resistance of 0.140 ω. when the switch is closed, a current of 600 ma occurs in the lamp. (a) what is the bulb's resistance?

Explanation:

It is given that,

Voltage of the battery, V = 1.5 V

Internal resistance of battery 1,

Internal resistance of battery 2,              

Current flowing in the lamp,

Total internal resistance of tow batteries,

Let R is the resistance of the bulb. Let V is the total emf of the circuit. It is given by :

So, the resistance of the bulb is 4.54 ohms. Hence, this is the required solution.                            

answer: a. same unit

explanation: