When the base current in a transistor is changed from `30 mu A`to `80 mu A`,the collector current is changed form 1.0 mA to 3.5 mA. Find the current gain `beta`.

Explanation

To find the current gain (β) of the transistor, we will follow these steps:

### Step 1: Calculate the change in base current (ΔIB)
The base current changes from 30 µA to 80 µA. We can calculate the change in base current as follows:

\[ \Delta I_B = I_{B2} - I_{B1} = 80 \, \mu A - 30 \, \mu A = 50 \, \mu A \]
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