1. What is an electrical current?

2. Calculate the current at the given points in each series circuit.

 

 

 

3. Calculate the voltage across the resistor in each of these series circuits.

 

 

 

4. In an experiment, two identical resistors are connected to a 9.0 V power supply. Calculate the voltage across each resistor.

 

 

 

 

 

 

 

 

5. Calculate the missing currents and voltages in these series circuits.

 

 

 

 

6. Calculate the current at the given points in each parallel circuit.

 

 

 

7. Calculate the voltage across the lamp in each of these parallel circuits.

 

 

 

 

8. In an experiment, two identical resistors are connected in parallel to a power supply which has 0.58 A drawn from it. Calculate the current through each resistor.

 

 

 

 

 

 

 

 

 

 

9. Calculate the missing currents and voltages in these parallel circuits.

 

 

 

10. A student designs the circuit shown to operate a 12 V, 3 A lamp from a 36 V supply.

 

(a) What is the reading on the ammeter when the lamp is operating at its correct power rating:’
(b) The resistance of Rx, is 2Ω. Calculate the voltage across Rx when the lamp is operating correctly
(c) Calculate the resistance of Ry when the lamp is operating correctly
(d) The student connects a second, identical lamp as shown in the diagram below:

 

 

 

Explain why the resistance of Ry has to be adjusted for both lamps to operate correctly.