Home
Class 12
PHYSICS
A change of 8.0mA in the emitter current...

A change of `8.0mA` in the emitter current brings a change of 7.9mA in the collector current. How much change in the base current is required to have the same change 7.9mA in the collector current?Find the values of `(alpha)`and `(beta)`.

Text Solution

Verified by Experts

We have
`I_E=I_B+I_C`
`or,(Delta)I_E=(Delta)I_B+(Delta)I_C`
Form the question,when (Delta)I_E=8.0mA,(Delta)I_C=7.9mA.`
Thus,
`(Delta)I_B=8.0mA-7.9mA=0.1mA.`
So a change of 0.1mA in the base current is required to have a change of 7.9mA in the collector current.
`(alpha)=I_(C)/I_(E)=(Delta)I_(C)/(Delta)I_(E)`
`7.9mA/8.0mA~~0.99.`
`(beta)=I_(C)/I_(B)=(Delta)I_(C)/(Delta)I_(B)`
`7.9mA/0.1mA=79.`
Check if these values of (alpha) and (beta)satisfy the equation
`(beta)=(alpha)/(1-(alpha)).`
Promotional Banner

Topper's Solved these Questions

  • SEMICONDUCTOR AND SEMICONDUCTOR DEVICES

    HC VERMA|Exercise Short Answer|11 Videos

  • SEMICONDUCTOR AND SEMICONDUCTOR DEVICES

    HC VERMA|Exercise Objective 1|13 Videos

  • SEMICONDUCTOR AND SEMICONDUCTOR DEVICES

    HC VERMA|Exercise Exercises|35 Videos

  • PHOTOMETRY

    HC VERMA|Exercise Exercises|16 Videos

  • SPEED OF LIGHT

    HC VERMA|Exercise Exercises|3 Videos

Similar Questions

Explore conceptually related problems

A transistor has an alpha = 0.95 It has change in emitter current of 100 mili-ampere, then the change in collector current is :-

The base current is 100 muA and collector current is 3 mA (a) Calculate the values of beta,I_(e) and alpha (b) A change of 20 muA in the base current produces a charge of 0.5 mA in the collector current. Caculate beta_(ac)

The current gain of a common base transistor circuit is 0.96. On changing the emitter current by 10.0 mA, the change in the base current will be .....

The current of transistor in common emitter mode is 49. The change in collector current and emitter current corresponding to the change in the base current by 5.0 muA m will be :-

A change of 0.04 V takes place between the base and the emitter when an input signal is connected to the CE transistor amplifier. As a result, 2014 change take place in the base current and a change of 2 mA lakes place in the collector current. Find the input resistance and A.C. current gain.

In npn transistor circuit, the collector current us 10 mA. If 95 % of the electrons emitted reach the collector what is the free current ?

Consider an n-p-n transistor amplifer in common-emitter configuration. The current gain of the transistor is 100 . If the collector current changes by 1mA , what will be the change in emitter current?

A variable frequency ac source is connected to a capacitor. How will the displacement current change with decrease in frequency ?

In a common base mode of a transition , the collector current is 5.488 mA for an emitter currect of 5.60 mA . The value of the base current amplification factor (beta) will be

In an NPN transistor the collector current is 10 mA . If 90% of electrons reach collector, the emitter current (i_(E)) and base current (i_(B)) are given by