In reality a transistor is generally added to the circuit to provide enough ... the coil has to go somewhere!). If the relay is attached parallel to a switch in some external device (such as ...

In the days before semiconductor diodes, transistors ... becomes conductive, the relay becomes energized and closes its switch. That switch activates the circuit that consists of the two ...

The mosfet is off if the input voltage is normally less than \(2.0 V\). By looking at a circuit diagram of a transistor switching circuit, you should be able to say what the circuit is used for ...