Question

In the circuit, what is the output voltage?

(a) 50 V

(b) 70 V

(c) 120 V

(d) 170 V

The question was posed to me in an international level competition.

My doubt stems from Zenner Diode topic in division Semiconductors of Engineering Physics II

Answer 1

Correct choice is (a) 50 V

Best explanation: In the absence of Zener diode, the open circuit voltage, V = RlVi/ R + Rl

 V = 80 V

Now, since the breakdown voltage of the Zener diode is 50 V, the diode will undergo breakdown

Output Voltage would be equal to 50 V.