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

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

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 output in the circuit shown in the figure taken across a capacitor is:

1.		2.
3.		4.

Logic gates \(X\) and \(Y\) have the truth tables shown below:

When the output of \(X\) is connected to the input of \(Y\), the resulting combination is equivalent to a single:
1. NOT gate
2. OR gate
3. NAND gate
4. AND gate

The LED: