A Zener diode voltage regulator operated in the range 120 V - 180 V produces a constant supply of 110 v and 250 aM to the load . If the maximum current is equally shared between the load and the Zener diode, then the values of load resistance `(R_(L))` and series resistance `(R_(S))` are respectively

Options

A. `R_(L) = 280 Omega,R_(S) = 70 Omega`
B. `R_(L) = 440 Omega,R_(S) = 140 Omega`
C. `R_(L) = 70 Omega,R_(S) = 280 Omega`
D. `R_(L) = 440 Omega,R_(S) = 1400 Omega`

Answer

B

Explanation

As current is eqully shared by Zener diode and resistance R
Then,
`I = 2 xx 250 = 500 mA`
= 0 . 5A
So, `R_(s) = (V_(s))/(I) = ((180 - 110))/(0 . 5) `
`= (70)/(0 . 5) = 140 Omega`