Question

A zener diode, having breakdown voltage equal to 15V, is used in a voltage regulator circuit shown in figure. The current through the diode is(a) 10 mA(b) 15 mA(c) 20 mA(d) 5 mA

Answer 1

Answer:

D) 5mA

Explanation:

Net Voltage = 20V  (Given)

Breakdown voltgae = 15V (Given)

Voltage across 1 KΩ = Voltage across Zener diode = 15 V

Current through 1 KΩ = 15 m A

If current through 250Ω is I, then the voltage across 250Ω P will be 5V.

Thus, according to the equation -

I = 5/250

I = 20

I = 20-15 = 5

Therefore the current through diode = 5mA