question_answer

A 24 V, 600 mW zener diode is used to provide a 24 V stabilized supply to a variable load \[{{R}_{L}}\], as shown in the figure. The value of the resistance R is

A)  \[320\,\,\Omega \]                       

B)  \[640\,\,\Omega \]

C)  \[960\,\,\Omega \]                       

D)  \[1280\,\,\Omega \]

Correct Answer: A

Solution :

                The voltage across R would be equal to \[32-24=8\,V\] Current flow across R,                 \[l=\left( \frac{P}{V} \right)=\frac{600\times {{10}^{-3}}}{24}=\frac{0.6}{24}A\] Now      \[R=\frac{V}{l}\]                               \[=\frac{8}{0.6}\times 24=320\,\,\Omega \]