$\mathrm{In} \mathrm{the} \mathrm{given} \mathrm{circuit} \mathrm{power}$
$\mathrm{developed} \mathrm{in} 1\mathrm{k\Omega } \mathrm{resistor} \mathrm{is}$

      ​​​​​​​

1.  36 mW

2.  12 mW

3.  144 mW

4.  64 mW

The given circuit has two ideal diodes connected as shown in the figure below. The current flowing through the resistance $R_1$ will be

1. 2.5 A                     

2. 10.0 A

3. 1.43 A                   

4. 3. 13 A

The given graph represents the $V\text-I$ characteristics of a semiconductor device. Which of the following statements is correct?
 

A Zener diode, having breakdown voltage equal to $15$ V, is used in a voltage regulator circuit, as shown in the figure. The current through the diode is:

                      
1. $10$ mA
2. $15$ mA
3. $20$ mA
4. $5$ mA

A p-n photodiode is fabricated from a semiconductor with a band gap of $2.5 \mathrm{eV}.$ It can detect a signal of wavelength 

1. $6000 \stackrel{\circ }{\mathrm{A}}$                                   
2. $4000 \mathrm{nm}$
3. $6000 \mathrm{nm}$                                 
4. $4000 \stackrel{\circ }{\mathrm{A}}$