Final answer:
In an active mode, the output of a transistor can be either less than or greater than the input, depending on the circuit configuration. An emitter-follower configuration typically has an output voltage less than the input, while a common emitter configuration can amplify and invert the input signal.
Step-by-step explanation:
When a transistor is in ACTIVE mode, the output can be either less than or greater than the input, depending on the configuration of the transistor circuit. In an emitter-follower configuration, the output is typically less than the input voltage, but with a higher current capability. This configuration is often used as a voltage buffer or impedance matching circuit.
On the other hand, in a common emitter configuration, the output can be amplified and inverted compared to the input. This configuration is commonly used in transistor amplifiers, where the output is generally greater than the input in terms of both voltage and current.
Therefore, whether the output is less than or greater than the input in active mode depends on the specific circuit configuration and the desired application.