The zener breakdown will occur if:

1.	the impurity level is low.
2.	the impurity level is high.
3.	the impurity is less on the \(\mathrm{n\text-}\)side.
4.	the impurity is less on the \(\mathrm{p\text-}\)side.

If the reverse bias in a junction diode is changed from \(5~\text V\) to \(15~\text V\) then the value of current changes from \(38~\mu \text{A}\) to \(88~\mu \text{A}.\) The resistance of the junction diode will be:
1. \(4\times10^{5}\) 
2. \(3\times10^{5}\)
3. \(2\times10^{5}\)
4. \(10^{6}\)

The figure shows a logic circuit with two inputs \(A\) and \(B\) and the output \(C\). The voltage waveforms across \(A\), \(B\), and \(C\) are as given. The logic circuit gate is:
         

1. \(\text{OR}\) gate
2. \(\text{NOR}\) gate
3. \(\text{AND}\) gate
4. \(\text{NAND}\) gate

An LED is constructed from a \(\mathrm{p\text{-}n}\) junction diode using \(\mathrm{GaAsP}.\) The energy gap is \(1.9~\text{eV}.\) The wavelength of the light emitted will be equal to:
1. \(10.4 \times 10^{-26}~ \text{m}\)
2. \(654~ \text{nm}\)
3. \(654~ \text{m}\)
4. \(654\times 10^{-11}~\text{m}\)