1. Why is it frustrating when one bulb burns out on a string of Christmas tree lights?

1. What happens to the current in the other two lamps if one lamp in a three-lamp series circuit is turned off? Why?

Problems

1. A 20 ohm and 5-ohm device are connected in series and attached to a 50 V battery.
   1. What is the total resistance of the circuit?
   2. What is the current in the circuit?
   3. What is the voltage across each device?
   4. What is the power of each device?

1. Three identical lamps are connected in series to a 6 V battery. What does the voltage drop across each individual lamp?

1. The load across a 12 V battery is a series of a 15-ohm, 21-ohm and 24-ohm devices.
   1. What is the total resistance of the load?
   2. What is the current in the circuit?

1. A battery is connected to a series circuit with a 15-ohm and 45-ohm resistor.
   1. What is the total resistance of the circuit?
   2. There is a current of 0.10 A in the circuit. What is the voltage of the battery?
   3. What is the voltage across each resistor individually?
   4. What is the power of each resistor individually?

1. A single lamp having a resistance of 10 ohms is connected to a 15 V battery.
   1. What is the current in the circuit?
   2. You need to reduce the current to 0.5 A. How much resistance should you connect to the circuit in series to make this happen?