Question 113: Semiconductors and Logic Gates

Question

The correct relation between $\alpha$ (ratio of collector current to emitter current) and $\beta$ (ratio of collector current to base current) of a transistor is :

Accepted Answer

$\alpha  = {{{I_C}} \over {{I_E}}}$ & $\beta  = {{{I_C}} \over {{I_B}}}$ & ${I_E} = {I_B} + {I_C}$
$ 	herefore $ ${{{I_E}} \over {{I_C}}} = {{{I_B}} \over {{I_C}}} + {{{I_C}} \over {{I_C}}}$
$ \Rightarrow {1 \over \alpha } = {1 \over \beta } + 1 = {{1 + \beta } \over \beta }$
$ \Rightarrow \alpha  = {\beta  \over {1 + \beta }}$

Answer

$\beta  = {\alpha  \over {1 + \alpha }}$

Answer

$\alpha  = {\beta  \over {1 - \alpha }}$

Answer

$\alpha  = {\beta  \over {1 + \beta }}$

Answer

$\beta  = {1 \over {1 - \alpha }}$

Semiconductors and Logic Gates

The correct relation between \alpha (ratio of collector current to emitter current) and \beta (ratio of collector current to base current) of a transistor is :

Choose the correct answer: