Two coils stand side by side on a bench. No wire joins them. The first coil's circuit has a battery and a switch. The second coil has only a meter across it.
While the current is steady, nothing is induced, even though the current still flows.
The first coil's switch has been closed for a minute, and 2 A flows steadily. What does the second coil's meter read?
An EMF is induced in the second coil only at the moments the first coil's current is changing.
A current that has flowed steadily for a minute is not changing.
The meter reads zero. The steady 2 A induces nothing.
The switch is now opened. What does the second coil's meter do at that instant, and afterward?
At the instant the switch opens, the first coil's current is changing.
After that instant, no current flows, so nothing is changing.
The meter kicks at the instant the switch opens, then returns to zero and stays there.
Two unconnected coils sit side by side. The first coil's switch is closed. What does the second coil's meter show at that instant?
The first coil's current now flows steadily at 3 A. What does the second coil's meter show?
Two unconnected coils sit side by side. The first coil's switch is opened. What does the second coil's meter show at that instant?
Two unconnected coils sit side by side. During which moments does the second coil's meter show a reading?
The current in the first coil flows steadily. Which statement about the nearby second coil is correct?
A dimmer knob smoothly raises the current in one coil. What does the voltmeter on a nearby coil show while the current is rising?