1. Calculate the current.
A 12 V ideal DC supply is connected across a 6 Ω resistor. What current flows through it, in amperes?
2. Calculate the potential difference.
A current of 0.25 A flows through a 40 Ω resistor. What is the potential difference across it, in volts?
3. Series circuits.
Resistors of 4 Ω and 8 Ω are connected in series across an ideal 24 V DC supply.
3(a). Find the total resistance.
3(b). Find the source current.
4. Parallel circuits.
Resistors of 6 Ω and 3 Ω are connected in parallel. Which is their equivalent resistance? Give the value, not the letter.
a. 9 Ω
b. 2 Ω
c. 3 Ω
d. 18 Ω
5. Power and energy.
An ideal DC load draws a constant 2 A at 12 V for 5 minutes.
5(a). Calculate its power in watts.
5(b). Calculate the energy transferred in joules.
6. Kirchhoff’s current law.
5 A enters a junction. One outgoing branch carries 1.5 A; the second carries the remaining current.
6(a). Find the second outgoing current.
6(b). State the conservation principle behind this law.