Question

The circuit contains two diodes, each with a forward resistance of  and with infinite backward resistance. If the battery voltage is 6 V, the current through the  resistance is  

                                                                        

Solution

Correct option is

0.02 A

 

The upper diode D1 is forward-biased (current flows in the direction of arrow) while the lower diode D2 is reverse-biased. Since resistance is infinite in reverse bias, no current flows in D2 arm. For the flow of current, the equivalent resistance will be as shown in the adjacent diagram.            

  

            = 0.02 A. 

                                                                 

SIMILAR QUESTIONS

Q1

The V-i characteristic of a silicon diode is given in the figure. Calculate the diode resistance in forward bias at V = +2 volt.  

Q2

A forward-biased p-n junction diode has a potential drop of 0.5 V which is assumed to be independent of current. The current in excess of 10 mA through the diode produces so much heating that burns the diode. If we have a 1.5 V battery to bias the diode, resistor must be used in series with the diode so that the maximum current does not exceed 5 mA?   

Q3

A Si diode (p-junction) is connected to a resistor R and a biasing battery of variable voltage VB. Assume that diode requires a maximum current of 1 mA to be above the knee point (0.7 V) of its V-i characteristic curve. Also assume that the voltage V across the diode is independent of current above the knee point. If VB = 5 V, what should be the maximum value of R so that the voltage V is above the knee-point voltage?   

                                                                  

Q4

In the circuit (a), calculate the current in the  resistance. Assume that each diode is of silicon (Si) and its potential barrier is 0.7 volt, and forward-resistance is .

Q5

p-n photodiode is fabricated from a semiconductor with a band gap of 2.8 eV. Can it detect a wavelength of 6000 nm?

  .

Q6

The depletion layer in the p-n junction is formed by

Q7

When a forward bias is applied to a p-n junction, it :

Q8

The resistance of a forward-biased p-n junction is :

Q9

When a semiconductor device is connected with a battery and a resistance in series, a current flows in the circuit. The current almost vanishes if the polarity of the battery is reversed. The device may be :

Q10

Two identical p-n junction may be connected in series with a battery in three ways. The potential drops across the two p-n junction are equal in :