Question:
In a Zener diode regulated power supply, unregulated d.c. input of $10$ V is applied. If the resistance $R_s$ connected in series with a Zener diode is $200\,\Omega$ and the Zener voltage $V_z = 5$ V, the current across the resistance $R_s$ is
In a Zener diode regulated power supply, unregulated d.c. input of $10$ V is applied. If the resistance $R_s$ connected in series with a Zener diode is $200\,\Omega$ and the Zener voltage $V_z = 5$ V, the current across the resistance $R_s$ is
Show Hint
Zener circuit: current = $\frac{V_{in} - V_z}{R}$.
Updated On: May 2, 2026
- $15$ mA
- $10$ mA
- $20$ mA
- $5$ mA
- $25$ mA
Show Solution
Verified By Collegedunia
The Correct Option is
Solution and Explanation
Concept: Zener diode voltage regulation
In breakdown region: \[ V_z = \text{constant} \] Voltage across resistor: \[ V_R = V_{in} - V_z \] ---
Step 1: Calculate voltage across resistor \[ V_R = 10 - 5 = 5 \text{ V} \] ---
Step 2: Apply Ohm's law \[ I = \frac{V_R}{R} \] \[ I = \frac{5}{200} = 0.025 \text{ A} \] ---
Step 3: Convert to mA \[ I = 25 \text{ mA} \] --- Physical Insight:
• Zener maintains constant voltage
• Excess voltage drops across resistor --- Final Answer: \[ \boxed{25 \text{ mA}} \]
In breakdown region: \[ V_z = \text{constant} \] Voltage across resistor: \[ V_R = V_{in} - V_z \] ---
Step 1: Calculate voltage across resistor \[ V_R = 10 - 5 = 5 \text{ V} \] ---
Step 2: Apply Ohm's law \[ I = \frac{V_R}{R} \] \[ I = \frac{5}{200} = 0.025 \text{ A} \] ---
Step 3: Convert to mA \[ I = 25 \text{ mA} \] --- Physical Insight:
• Zener maintains constant voltage
• Excess voltage drops across resistor --- Final Answer: \[ \boxed{25 \text{ mA}} \]
Was this answer helpful?
0
0
Top KEAM Physics Questions
- A body oscillates with SHM according to the equation (in SI units), $x = 5 cos \left(2\pi t +\frac{\pi}{4}\right) .$ Its instantaneous displacement at $t = 1$ second is
Kepler's second law (law of areas) of planetary motion leads to law of conservation of
- Two capillary tubes A and B of diameter $1\, mm$ and $2\, mm$ respectively are dipped vertically in a liquid. If the capillary rise in A is 6 cm, then the capillary rise in B is
- In the circuit given in figure, 1 and 2 are ammeters. Just after key K is pressed to complete the circuit, the reading will be
- A plate has a length $ 5\pm 0.1\text{ }cm $ and breadth $ 2\pm 0.01\text{ }cm $ . Then the area of the plate is:
View More Questions
Top KEAM applications of diode Questions
- The light emitting diode $(LED)$ is
- A pn junction diode without bias acts as:
- An alternating voltage of \( 250\,\text{V},\,50\,\text{Hz} \) is applied to a full wave rectifier. If the internal resistance of each diode is \( 10\,\Omega \) and the load resistance is \( 5\,\text{k}\Omega \), the peak value of output current is
- The reverse biasing in a junction diode,
- Ripple frequency of a full wave rectifier is
View More Questions
Top KEAM Questions
- i.$\quad$ They help in respiration ii.$\quad$ They help in cell wall formation iii.$\quad$ They help in DNA replication iv. $\quad$They increase surface area of plasma membrane Which of the following prokaryotic structures has all the above roles?
- A body oscillates with SHM according to the equation (in SI units), $x = 5 cos \left(2\pi t +\frac{\pi}{4}\right) .$ Its instantaneous displacement at $t = 1$ second is
- The pH of a solution obtained by mixing 60 mL of 0.1 M BaOH solution at 40m of 0.15m HCI solution is
Kepler's second law (law of areas) of planetary motion leads to law of conservation of
- If $\int e^{2x}f' \left(x\right)dx =g \left(x\right)$, then $ \int\left(e^{2x}f\left(x\right) + e^{2x} f' \left(x\right)\right)dx =$
View More Questions