A coil of wire with a large current flowing through it. Electrical power is supplied to your house as an alternating current because it is easy to change the voltage of an alternating current without wasting much energy. The same amount of power can be delivered to your house using a large voltage and a small current or a small voltage and a large current. Compare the number of turns in the primary coil in this transformer to the number of turns in the secondary coil. Briefly describe how power is transferred between the primary and secondary circuits of the transformer.
Some electronic devices require a direct rather than alternating current.
This lamp requires 6 volt electricity. You can power it either with four 1.5 volt batteries in a battery pack or with a little step-down transformer that plugs into the electric outlet and produces 6 volt alternating current. There are two wires connecting the battery pack to the lamp. When you operate the lamp from the transformer, there are moments when the lamp receives no electric power. With your tremendous understanding of physics, you've received many lucrative offers to help the scoundrels, but you've held fast to the traditions of the UVa honor system and refused them all.