Question

For the given circuit the power dissipated by Zener diode is

• A. $20W$
• B. $15W$
• C. $10W$
• D. $0W$

Answer 1

Answer: (D)

Current flowing through load resistor is given as $i=\frac{16}{1000 + 1200}=7.2mA$
Voltage drop across the load resistor, $V_{a b}=iR_{L}=7.2\times 10^{- 3}\times 1200=8.72V$ .
As $V_{a b} < 10V$
So, breakdown of zener diode does not occur and no current flows through it.
So, $I_{z}=0$ and $P_{z}=I_{Z}V_{z}=0W$