Advertisements
Advertisements
प्रश्न
Find the equivalent resistance of the network shown in figure between the points A and B.

(Assume that the resistance of each diode is zero in forward bias and is infinity in reverse bias.)
Advertisements
उत्तर
Let the potentials at A and B be VA and VB, respectively.
(i) When VA > VB, that is, a battery is connected between points A and B, with its positive terminal connected to point A and its negative terminal connected to point B:
As the potential on the p-side of the diode is greater than the potential on the n-side of the diode, the diode is forward biased; thus, it can be replaced by a short circuit.
As the two resistances are connected in parallel, the effective resistance becomes
Equivalent resistance \[= \frac{10}{2} = 5 \Omega\]
(ii) When VA < VB:
The diode is reverse biased, so it is replaced by an open circuit. Thus, no current flows through this branch.
∴ Equivalent resistance = 10 Ω
APPEARS IN
संबंधित प्रश्न
Explain briefly with the help of necessary diagrams, the forward biasing of a p-n junction diode. Also draw characteristic curves.
Explain briefly with the help of necessary diagrams, the reverse biasing of a p-n junction diode. Also draw characteristic curves.
A student wants to use two p-n junction diodes to convert alternating current into direct current. Draw the labelled circuit diagram she would use and explain how it works.
Explain, with the help of a circuit diagram, the working of n-p-n transistor as a common emitter amplifier.
How is a zener diode fabricated so as to make it a special purpose diode? Draw I-V characteristics of zener diode and explain the significance of breakdown voltage.
Explain briefly, with the help of a circuit diagram, how a p-n junction diode works as a half wave rectifier.
The drift current in a reverse-biased p-n junction is increased in magnitude if the temperature of the junction is increased. Explain this on the basis of creation of hole-electron pairs.
The drift current in a p-n junction is
Two identical p-n junction may be connected in series with a battery in three ways. The potential difference across the two p-n junctions are equal in

In a p-n junction,
(a) new holes and conduction electrons are produced continuously throughout the material
(b) new holes and conduction electrons are produced continuously throughout the material except in the depletion region
(c) holes and conduction electrons recombine continuously throughout the material
(d) holes and conduction electrons recombine continuously throughout the material except in the depletion region.
A semiconducting device is connected in a series circuit with a battery and a resistance. A current is found to pass through the circuit. If the polarity of the battery is reversed, the current drops to almost zero. the device may be
(a) an intrinsic semiconductor
(b) a p-type semiconductor
(c) an n-type semiconductor
(d) a p-n junction
In a p.n junction, the depletion region is 400 nm wide and an electric field of 5 × 105 V m−1 exists in it. (a) Find the height of the potential barrier. (b) What should be the minimum kinetic energy of a conduction electron which can diffuse from the n-side to the p-side?
In a p-n junction, a potential barrier of 250 meV exists across the junction. A hole with a kinetic energy of 300 meV approaches the junction. Find the kinetic energy of the hole when it crosses the junction if the hole approached the junction (a) from the p-side and (b) from the n-side.
Calculate the current through the circuit and the potential difference across the diode shown in figure. The drift current for the diode is 20 µA.

Find the current through the battery in each of the circuits shown in figure.

(Assume that the resistance of each diode is zero in forward bias and is infinity in reverse bias.)
Draw the current-voltage characteristics for the device show in figure between the terminals A and B.

(Assume that the resistance of each diode is zero in forward bias and is infinity in reverse bias.)
An AC source is connected to a diode and a resistor in series. Is the current thorough the resistor AC or DC?
If in a p-n junction diode, a square input signal of 10 V is applied as shown Then the output signal across RL will be ______
In a semiconductor diode, the barrier potential offers opposition to only ______.
The formation of the depletion region in a p-n junction diode is due to ______.
