A forward-biased diode is treated as:

1.	an open switch with infinite resistance.
2.	a closed switch with a voltage drop of \(0\) V.
3.	a closed switch in series with a battery with voltage of \(0.7\) V.
4.	a closed switch in series with small resistance and a battery.

If the input to the NOT gate is \(A\), its output is:
1. \(0\)
2. \(1\)
3. \(A\)
4. \(\overline{A}\)

For a transistor amplifier, the voltage gain:

In a half-wave rectification, what is the output frequency if the input frequency is \(50~\text{Hz}?\)
1. \(50~\text{Hz}\)
2. \(100~\text{Hz}\)
3. \(25~\text{Hz}\)
4. \(60~\text{Hz}\)

In the energy band diagram of a material shown below, the open circles and filled circles denote holes and electrons respectively. The material is a/an: 
      

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

Find the base resistance ${\mathrm{R}}_{\mathrm{B}}$ in the circuit below, if \(\beta_{DC} =90\) and \(V_{BE}=0.7~V.\)
       
1. 83 $\mathrm{\Omega }$

2. 41 k$\mathrm{\Omega }$

3. 83 k$\mathrm{\Omega }$

4. 41 $\mathrm{\Omega }$

The combination of gates shown below is equivalent to:
                
1. AND gate
2. XOR gate
3. NOR gate
4. NAND gate