In a common emitter transistor, the current gain is `80`. What is the change in collector current, when the change in base current is `250 muA`?

Options

A. `80 xx 250muA`
B. `(250-80)muA`
C. `(250+80)muA`
D. `250 muA`

Answer

To solve the problem step by step, we will use the relationship between the change in collector current (ΔIc), the change in base current (ΔIb), and the current gain (β) of the transistor.

### Step 1: Understand the relationship
The current gain (β) in a common emitter transistor is defined as the ratio of the change in collector current (ΔIc) to the change in base current (ΔIb). This can be expressed mathematically as:
\[ \beta = \frac{\Delta I_c}{\Delta I_b} \]

### Step 2: Rearrange the formula
To find the change in collector current (ΔIc), we can rearrange the formula:
\[ \Delta I_c = \beta \times \Delta I_b \]

### Step 3: Substitute the known values
From the problem, we know:
- The current gain (β) = 80
- The change in base current (ΔIb) = 250 μA (microamperes)

Now, substituting these values into the equation:
\[ \Delta I_c = 80 \times 250 \, \mu A \]

### Step 4: Perform the calculation
Now we calculate ΔIc:
\[ \Delta I_c = 80 \times 250 = 20000 \, \mu A \]

### Step 5: Convert to milliamperes (optional)
Since 1 mA = 1000 μA, we can convert the result:
\[ \Delta I_c = 20000 \, \mu A = 20 \, mA \]

### Final Answer
The change in collector current (ΔIc) is **20000 μA** or **20 mA**.