Q 12-14-043JEE MainJEE Main 2026 (4 Apr, Shift 2)Easy
A diode has Zener voltage of $10$ V and maximum power dissipation of $0.5$ W, then the minimum resistance to be used in series with this diode for safety when it is connected to a $25$ V power supply is ______ $\Omega$.
Numerical value type. Enter your answer.
Answer: 300
Maximum Zener current: $I = \dfrac{0.5}{10} = 0.05$ A.
The series resistor drops $25 - 10 = 15$ V, so $R_{\min} = \dfrac{15}{0.05} = 300\ \Omega$.
Solution by Sreeraj P, M.Sc Physics