Question

A transistor is working in common emitter mode. Its amplification factor ($β$) is 80. If the base current is 250 $μ A$, the collector current will be

• A. $1.25 \mu A$
• B. $\frac{250}{80} \mu A$
• C. $430 \mu A$
• D. $250 \times 80 \mu A$

Hint:

A transistor is working in common emitter mode. Its amplification factor ($β$) is 80. If the base current is 250 $μ A$, the collector current will be

Answer 1

The Correct Option is D

To find the collector current (\(I_c\)) in a common emitter transistor configuration, we use the relation between the base current (\(I_b\)), collector current (\(I_c\)), and the current amplification factor, denoted as β (beta).

The formula for the collector current is given by:

\(I_c = β \times I_b\)

Given:

• Base current, \(I_b = 250 \, \mu A\)
• Current amplification factor, \(β = 80\)

Substitute these values into the formula:

\(I_c = 80 \times 250 \, \mu A\)

Calculate the product:

\(I_c = 20000 \, \mu A = 20 \, mA\)

Based on the given options, the correct choice matches with \(250 \times 80 \, \mu A\).

Thus, the collector current is \(20 \, mA\).