Explanation:

To understand the relationship between gm (transconductance) and Ica (collector current), we need to first understand what transconductance and collector current are.

- Transconductance (gm): Transconductance is a parameter that relates the change in the output current (Ic) to the change in the input voltage (Vbe) of a transistor. It measures the amplification capability of a transistor. Transconductance is given by the equation gm = dIc/dVbe, where dIc represents the change in collector current and dVbe represents the change in base-emitter voltage.

- Collector Current (Ica): The collector current is the current flowing through the collector terminal of a transistor.

Now, let's analyze the relationship between gm and Ica.


When two variables are directly proportional, it means that as one variable increases, the other variable also increases by the same factor, and vice versa.

In the case of gm and Ica, the relationship is directly proportional. This means that as the transconductance (gm) of a transistor increases, the collector current (Ica) also increases by the same factor. Similarly, if gm decreases, Ica will also decrease.

The direct proportionality between gm and Ica can be explained by the transistor's operating characteristics. As gm increases, it means the transistor has a higher amplification capability. This results in a larger change in the collector current for a given change in the base-emitter voltage. Therefore, the collector current increases.

Conversely, if gm decreases, it means the transistor has a lower amplification capability. This leads to a smaller change in the collector current for a given change in the base-emitter voltage, resulting in a decrease in the collector current.

Therefore, the relationship between gm and Ica is directly proportional.