Question
In an npn transistor, 10^{10} electrons enter the emitter in 10^{–6} s. 2% of the electrons are lost in the base. Calculate the current transfer ratio and the current amplification factor. Charge on electron is .

1.30, 75

1.50, 65

0.98, 49

None of these
diffcult
Solution
0.98, 49
The current is rate of flow of change (q/t). Since 10^{10} electrons enter the emitter in 10^{–6} s, the emittercurrent is
= 1.6 mA.
Similarly, the basecurrent is
= 0.032 mA.
In transistor, the emitter current is the sum of the base current and the collector current .
= 1.6 mA – 0.032 mA
= 1.568 mA.
The current transfer ratio is
= 0.98.
The current amplification factor is
= 49.
SIMILAR QUESTIONS
In a pnp transistor with normal bias:
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In input and output resistances in a commonbase amplifier circuit are respectively. If the currentgain is 0.98, then find the voltage gain. If the emittercurrent is 2 mA, then find the collectorcurrent and the basecurrent.
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Find the voltage gain and power gain in a transistor amplifier in commonemitter configuration when and the input and the output ersistance are .
The input resistance of a silicon transistor is . Its basecurrent is changed by which results in a change of 2 mA in the collectorcurrent. The transistor is used as a commonemitter amplifier with a load resistance of . What is the voltage gain of the amplifier? Also calculate the transconductance of the transistor.
A change of 0.2 mA in basecurrent causes a change of 5 mA in the collectorcurrent for a commonemitter amplifier. Find the ac current gain of the transistor.
A transistor is connected in commonemitter configuration. The collectorsupply is 8 V and the voltage drop across a resistor of in the collector circuit is 0.5 V. If the currentgain factor is 0.96, find the basecurrent.