In the voltage regulator shown in the figure, the load current can vary from 100 mA to 500 mA. Assuming that the Zener diode is ideal (i.e. The Zener knee current is negligibly small and Zener resistance is Zero in the breakdown region), the value of R is
1
7 Ω
2
70 Ω
3
70/3 Ω
4
14 Ω
5
140 Ω