Question

A zener diode has break down voltage of 5.0 V. The resistance required to allow a current of 100 mA through the zener in reverse bias when connected to a battery of emf 12 V is

• A. 50 $\Omega$
• B. 70 $\Omega$
• C. 100 $\Omega$
• D. 150 $\Omega$

Answer 1

Answer: (B)

70 $\Omega$

Answer 2

V = IR
$\left(12-5\right)V =7V =100 \times10^{-3}\times R$
$7=10^{-1}\times R$
$R=70\Omega$