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The answer is Holes.

(i) Ac drain resistance (r_d) is the ratio of small change in drain to source voltage V_DS to the corresponding change in drain current (I_D) for a constant V_GS.

(ii) Transconductance (g_m) is the ratio of change in drain current I_D to the corresponding change in gate to source voltage V_GS for a constant V_DS.

The relation between p, r_d, and g_m is:

u = r_d x g_s

Field effect transistor is a three-terminal device in which the flow of current is controlled by an applied electric field.

Drain characteristics is set of curves drawn for the relationship between drain current (I_D) and drain to source voltage (V_DS) at a constant gate to source voltage (V_GS).

The negative gate voltage at which drain current becomes zero.

Negative potential.

(i) Drain characteristics

(ii) Transfer characteristics.

The value of drain current at pinch off condition is Zero.

Pinch off voltage is the gate voltage at which the drain current is zero.

It is the ratio of change in drain current I_D to the corresponding change in gate to source voltage V_GS for a constant drain to source voltage V_DS.

Drain collects the charge carriers supplied by the source.

Source supplies charge carriers for conduction.

The answer is Free electron.

N channel FET has free electrons as charge carriers and p channel FET has holes as charge carriers.

FET is a Unipolar device.

When the gate is reverse biased, the depletion regions are extended towards the channel by the application of reverse bias voltage. When V_GS = OV, is when gate terminal is open, the drain current is maximum and flows from drain to source called L_Dss . If V_Gs is increased, the reverse bias across the junction increases reducing the width of the channel.

This makes the drain current decrease. Further increase in the reverse bias voltage widens the depletion region and the drain current I_D further decreases. Thus the drain current in the device is mainly controlled by the reverse voltage applied across the gate-to-source voltage.

For fabricating p-channel FET, first a narrow bar of p type semiconductor material is taken and then two pn junctions are diffused on opposite sides of its middle part. These junctions form two pn junctions and area between these gates is called the channel.

The two p regions are internally connected and a single lead is brought out which is called gate terminal. Ohmic contacts are made at the two ends of the bar called source terminals and the other drain terminal D.

It is the ratio of change in drain to source voltage V_DS to a corresponding change in gate to source voltage V_GS for constant drain current I_D.

Gate controls the flow of charge carriers through the channel.

Two pn junctions.

In channel FET has n type semiconductor bar with two p type heavily doped regions diffused on opposite sides.

These are the set of curves drawn for the relationship between drain current (I_D) and gate to source voltage (V_GS) at a constant drain to source voltage (V_DS).

p channel FET has p type semiconductor bar with two n type heavily doped regions diffused on opposite sides.

Drain collects the charge carriers supplied by the source. Gate controls the flow of charge carriers through the channel.

Metal oxide semiconductor Field Effect Transistor.

Junction Field Effect Transistor.

The drain resistance is the ratio of drain to source voltage V_DS to the drain current I_D for a constant value of gate to source voltage V_GS.

(i) Junction FET

(ii) Metal oxide semiconductor FET.

FET = Field Effect Transistor
MOSFET = Metal oxide semiconductor Field Effect Transistor.

I_DSS is the drain to source saturation current.

Insulated Gate Field Effect Transistor.

FET is voltage controlled device.

FET can be fabricated with either n-channel or p-channel. For fabricating n-channel FET, first a narrow bar of n type semiconductor material is taken and then two pn juntions are diffused on opposite sides of its middle part.

These junctions form two pn junctions and area between these gate is called channel. The two p regions are internally connected and a single lead is brought out which is called gate terminal. Ohmic contacts are made at the two ends of the bar called source terminals and the other drain terminal D.

(i) Junction field effect transistor (JFET).

(ii) Metal oxide semiconductor field effect transistor (MOSFET) or Insulated gate field effect transistor (IGFET).

Gate, Drain, and Source.

FET is a voltage controlled device.

Amplification factor is the ratio of small change in drain source voltage to the corresponding change in gate to source voltage for a constant drain current.
μ = r_d  g_m

FET stands for Field Effect Transistor.

Amplification factor is the ratio of change in drain to source voltage to corresponding change in gate to source voltage for a constant drain current.

Transconductance is the ratio of small change in drain current (I_D) to the corresponding change in gate to source voltage (V_GS) for a constant drain to source voltage.

g_m = g_mo[\(1-\frac{V_{GS}}{V_P}\)]

Drain resistance is the ratio of change in drain to source voltage to corresponding change in drain current for a constant gate to source voltage.

Transconductance is the ratio of change in drain current to corresponding change in gate to source voltage for a constant drain to source voltage.

The commercial unit of electric energy is the kilowatt hour (kW·h) and the SI unit of energy is the joule (J).

1 kW·h = 10³ \(\frac{J}{s}\) × 3600 s s

= 3.6 × 10⁶ J

[Note: The kilowatt-hour is often called simply the unit. (See the energy bill, i.e., the electricity bill.)]

Electric motor:

1. A battery is used in an electric motor to pass a current through the coil.

2. In this case, a current-carrying coil is set in rotation due to the magnetic field.

3. Split rings are used in an electric motor.

4. In this case, electric energy is converted into mechanical energy.

Electric generator:

1. A battery is not used in an electric generator. 

2. In this case, a potential difference and hence a current is produced when the coil is set into rotation in the magnetic field by an external agent. 

3. Rings used in an AC generator are not split. 

4. In this case, mechanical energy is converted into electric energy.

(c) haemozoin

Short circuiting: When electric circuit offers very low resistance to the flow of current through it, the current increases heavily and the circuit is said to be short circuited. It occurs when live wire touches the neutral wire. This happens due to the damage in insulation of the power lines.

Safety measure device: Fuse. 

Working principle of fuse: It works on the heating effect of electric current or Joule’s law of heating. According to this law, the heat produced in a resistor is directly proportional to the 

(i) square of current for a given resistance. 

(ii) resistance for a given current and 

(iii) time for which the current flows through the resistor. H = I²Rt

So, when current in the circuit increases, the wire with low melting point in it melts to the heat generated. Hence, the circuit breaks and electrical devices and appliances are saved.