Semi conductor devices practice · Mixed difficulty

The dominant mechanism for motion of charge carriers in forward and reverse biased silicon P-N junctions are

Assertion(A): Photodiodes are preferably
used in the reverse bias condition for
measuring light intensity.

Reason(R): The fractional change due to the
photo-effects on the minority carrier
dominated reverse bias current is more easily
measurable than the fractional change in the
forward bias current.

Assertion : Photodiode & photovoltaic cell are based on the same principle.

Reason : Both use same method of operations to work.

The overall gain of a multistage amplifier is 100. When negative feedback is applied, the gain reduces to 10 . Find the fraction of the output that is feedback to the input.

In a triode amplifier, the value of maximum gain is equal to

The main cause of zener breakdown is

Statement-I: In Zener diode depletion layer is thin.

Statement-II: In reverse bias, strong electric field exists across the potential barrier.

Carbon, silicon and germanium atoms have four valence electrons each. Their valence and conduction bands are separated by energy band gaps represented by $\left(E_g\right)_{{C}},\left(E_g\right)_{{Si}}$ and $\left(E_g\right)_{{Ge}}$, respectively. Which one of the following relationship is true in their case?

Metallic solids are always opaque because

Choose the correct statement

In which of the following ionic bond is present

A semiconductor device is connected in a series circuit with a battery and a resistance. A current is found to pass through the circuit. If the polarity of the battery is revered, the current drops almost to zero. The device may be

Statement I: By doping silicon semiconductor with pentavalent material the electrons density increases.
Statement II: The $n$-type semiconductor has net negative charge.
In the light of the above statements choose the most appropriate answer from the options given below.

Assertion: Electron has higher mobility than hole in a semiconductor.
Reason: Mass of electron is less than the mass of hole

Semiconductor is damaged by the strong current due to

When the forward bias voltage of a diode is changed from 0.6 V to 0.7 V, the current changes from 5 mA to 15 mA. Then its forward bias resistance is

In the study of transistor as an amplifier, if $\alpha = {I_c}/{I_e}$ and $\beta = {I_c}/{I_b}$, where ${I_c},{I_b}$ and ${I_e}$ are the collector, base and emitter currents, then

A half wave rectifier is used to convert 80 Hz A.C into D.C voltage the number of pulses per second in the rectified voltage are

In a solar cell current is generated due to bond breakage in
which region.

When a battery is connected to a $P$-type semiconductor with a metallic wire, the current in the semiconductor (predominantly), inside the metallic wire and that inside the battery respectively is due to

Assertion : In solar cell it is imperative (essential) that photo generation of electrons and holes occurs in depletion region.

Reason : The junction Field separates electron hole pair effectively.

In a junction diode, the direction of diffusion current is

Zener diode is used as

In a P-type semiconductor, the acceptor impurity produces an energy level

Diode valve is discovered by

LED is a $p$-$n$ junction diode which is

To measure light intensity we use

If $\mathrm{\alpha \;and\;\beta }$ are the collector emitter short circuit current amplification factor and collector base short circuit current amplification factor respectively of a transistor then $\mathrm{\alpha }$ is equal to

The peak voltage in the output of a half wave diode rectifier fed with a sinusoidal signal without filter is $10 \, {~V}$. The D.C. component of the output voltage is :

In a semiconductor