Advertisements
Advertisements
प्रश्न
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.)
Advertisements
उत्तर
We know that when a diode is forward biassed, it has zero resistance ideally. So, it can be replaced by a short circuit. When a diode is reverse biassed, it has infinite resistance ideally. So, it can be replaced by an open circuit.
(a) In the given circuit diagram, both diodes are forward biassed. So, the resistance of both of them is zero. Thus, the diode resistance is zero.
\[i = \frac{5}{\frac{10 \times 10}{10 + 10}} = \frac{5}{5} = 1 A\]
(b) One diode is forward biassed and the other is reverse biassed. The reverse-biassed diode is replaced by an open circuit, so no current flows through this branch.
The current passes through the forward-biassed diode only.
\[i = \frac{V}{R_{net}} = \frac{5}{10} = 0 . 5 A\]
APPEARS IN
संबंधित प्रश्न
Explain, with the help of a circuit diagram, the working of a photo-diode. Write briefly how it is used to detect the optical signals.
When a p-type impurity is doped in a semiconductor, a large number of holes are created, This does not make the semiconductor charged. But when holes diffuse from the p-side to the n-side in a p-n junction, the n-side gets positively charged. Explain.
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.
Diffusion current in a p-n junction is greater than the drift current in magnitude
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 with open ends,
(a) there is no systematic motion of charge carries
(b) holes and conduction electrons systematically go from the p-side to n-side and from the n-side to p-side respectively
(c) there is no net charge transfer between the two sides
(d) there is a constant electric field near the junction.
The potential barrier existing across an unbiased p-n junction is 0.2 volt. What minimum kinetic energy a hole should have to diffuse from the p-side to the n-side if (a) the junction is unbiased, (b) the junction is forward-biased at 0.1 volt and (c) the junction is reverse-biased at 0.1 volt?
When a p-n junction is reverse-biased, the current becomes almost constant at 25 µA. When it is forward-biased at 200 mV, a current of 75 µA is obtained. Find the magnitude of diffusion current when the diode is
(a) unbiased,
(b) reverse-biased at 200 mV and
(c) forward-biased at 200 mV.
Each of the resistance shown in figure has a value of 20 Ω. Find the equivalent resistance between A and B. Does it depend on whether the point A or B is at higher potential?
When the base current in a transistor is changed from 30µA to 80µA, the collector current is changed from 1.0 mA to 3.5 mA. Find the current gain β.
A load resistor of 2kΩ is connected in the collector branch of an amplifier circuit using a transistor in common-emitter mode. The current gain β = 50. The input resistance of the transistor is 0.50 kΩ. If the input current is changed by 50µA. (a) by what amount does the output voltage change, (b) by what amount does the input voltage change and (c) what is the power gain?
An AC source is connected to a diode and a resistor in series. Is the current thorough the resistor AC or DC?
Answer in detail.
Discuss the effect of external voltage on the width of depletion region of a p-n junction.
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 ______
For an ideal diode, in forward and reverse biased condition the resistance is respectively ______.
In p-n junction diode ______.
What is barrier potential?
Why does microscopic roughness prevent a proper crystal lattice from forming between separate p-type and n-type slabs?
How does the interface between physically joined p-type and n-type slabs act on charge carriers?
What is the approximate knee voltage for silicon?
