Q&A - Ask Doubts and Get Answers
Q

Need explanation for: A working transistor with its three legs marked P ,Q and R is tested using a multimeter. No conduction is found between P and Q . By connecting the common (negative) terminal of the multimeter to R and the other (positive) termi

A working transistor with its three legs marked P ,Q and R  is tested using a multimeter. No conduction is found between P and Q . By connecting the common (negative) terminal of the multimeter to R and the other (positive) terminal to P or Q , some resistance is seen on the multimeter. Which of the following is true for the transistor?

  • Option 1)

    It is an npn transistor with R as collector.

  • Option 2)

    It is an npn transistor with R as base.

  • Option 3)

    It is an pnp transistor with R as collector.

  • Option 4)

    It is an pnp transistor with R as emitter.

 
Answers (1)
937 Views

As we learnt in

Transistor -

Three layered semiconducting device .

NPN or PNP

- wherein

1.    Emitter is heavily doped

2.    collector is moderately doped .

3.    Base is lightly doped & very thin

 

 Since by connecting R to negative terminal and P or Q to positive terminal, there is some resistance and hence it is in forward biased mode. 

Hence, R has to be -n type.

R is collector and the transistor is npn.

Correct option is 1.

 


Option 1)

It is an npn transistor with R as collector.

This is the correct option.

Option 2)

It is an npn transistor with R as base.

This is an incorrect option.

Option 3)

It is an pnp transistor with R as collector.

This is an incorrect option.

Option 4)

It is an pnp transistor with R as emitter.

This is an incorrect option.

Exams
Articles
Questions