Noob Robo

Purpose:- Estimation of total chlorophyll by Arnon's method. Requirement:- Spectrophotometer Buchner's funnel, filter paper test tube, Fresh leaves. measuring cylinder pestle & mortar 80% Acetone  Formula:- 20.2 (A645) +802 A663) / 1000 x W Principle:- Chlorophyll is extracted in 80% acetone & the absorption at 660 nm& 645 nm are read in s spectrophotometer using the absorption co-efficient, the amount of chlorophyll is calculated Procedure:- 1) Weigh 1 gm of finely cut & well mixed representative sample of a leaf or fruit tissue into a clean mortar 2) Grind the tissue to a fine pulp with the addition of 20mil of 80% acetone   3) Centrifuge (5000 rpm for 5 min) & transfer the supernatant to a 100 ml volumetric flask  4) Repeat this procedure until the residue is colorless wash the mortar and pestle  thoroughly with 80% acetone and collect the clear washing in the volumetric flask 5) Make up the volume to 100 ml with 80% acetone  6) ...

Aim:-  To determine Planks constant by black body radiation method    Apparatus:- Ammeter, Voltmeter, Black body radiator, connecting wires. Theory:-   As per planks, quantum theory energy is radiated in packets of energy called quanta, each quantum has the energy of hϑ where h is Plank's constant  (h=6.625× 10 -34  Js) Procedure:- 1)The electrical connections  made as shown in the circuit diagram. 2) The black body radiator is preheated to  30 0 c  by setting maximum voltage in the power supply. 3) After the temperature indicator indicates a temperature of about  30 0 c  the voltage is reduced to some value. 4) increase the voltage in steps of 0.2 V and note down the current, hence calculate the power. 5)Hence calculate Stefan's constant and thereby Planks constant. Observations:- 1) Boltzmann constant k=1.38× 10 -23 J/K 2) Velocity of light c=3×10-8 m/sec  Calculation:- h= ∛2 π 5 k 4 / 15σc 2 Result:-  *Standar...

Aim:-  To determine the value of Stefan's constant. Apparatus:-  Black body radiation unit, Ammeter, Voltmeter, connecting wires, DC source. Theory:-  Stefan's constant: A physical constant denoted by  σ , is the constant of proportionality in the Stefan's-Boltzmann law- the total intensity radiated over all wavelength increases as the temperature increases Procedure:- 1) The electrical connections are made as shown in the circuit diagram. 2) Copper black body radiator is preheated to  30 0 C   by setting maximum voltage in the power supply 3)after the temperature indicator indicates a temperature of about    30 0 C , the voltage is reduced to some value  4) increase the voltage in steps of 0.2 V and note down the current, hence calculate power l. 5) Determine the value of Stefan's constan t. Observations:-  Room temperature t o =t+273=......of 2) surface area of the black body  A=4π r 2  = .........m square Calculati...

Aim: -  To determine and set up a Weing bridge oscillator using BJT and to observe the sinusoidal output waveform. Apparatus: -  transistor, resistor, capacitor, bread board, connecting wire. Theory: -  A wein bridge oscillator is a type of electronics oscillator that generates a sine wave. It can generate a large range of frequencies. The bridge comprises four resistors and capacitors. The oscillator can also be viewed as appositive gain amplifies combined with a bandpass filter that provides positive feedback. To view the Tabular column click here Procedure:- 1) Set up the circuit, on a breadboard, as shown in the figure. 2) Switch on Dc source and observe output waveforms on CRO 3) Measure the frequency of oscillation f. 4) Try different values of R and C compare the computed and measured frequency.            Result:-       Theoretical frequency  =  __________ Hz      Pr Practical fr...

Aim: - To determine the frequency of the RC phase shift oscillator. Apparatus: - BJT, resistor, capacitor, CRO, breadboard, connection wire Principle: - The BJT picks up small fluctuations at the input and amplifies them with a 180-degree phase shift    Theory:- An oscillator converts AC to DC RC phase shift oscillator uses there identical RC blocks which act as feedback of oscillation is given by f= 1/1/2πRC√6         Procedure:- Identify the pin details of the transistor and test it using a millimeter. Set up the circuit on the breadboard as shown in the figure. Calculate the frequency from CRO display f=1/T Verify the practical frequency with the theoretical value.   Calculation:- Theoretical frequency: -      f=1/2πRC√6   Result: - The frequency of the RC phase shift oscillator is determined and verified with the theoretical value. They are nearly equal.

Aim:- To obtain the V-I characteristics of SCR and find the break over voltage holding current. Apparatus: - Ammeter, resistor, Voltammeter, breadboard, wires, SCR. Theory: -   A silicon controlled rectifier (SCR) is a semiconductor device that acts as a true electronic switch. It can change the alternating current into a direct current. It can control the amount of power fed to the load. Thus the SCR combines the feature of the rectifier and a transistor. If the supply voltage is less than the break over-voltage, the gate will open. Then increase the supply voltage from zero, a point is reached when the SCR starts conducting. Under this condition, the voltage across the SCR suddenly drops and most of the supply voltage appears across the load resistance R L . If proper gate current is made to flow the SCR can close at a much smaller supply voltage. V AK  = _______ Trigger count =I G=_______________   Procedure:- 1)    Set the V Now increase I G ...

Purpose: - To study and plot the BJT characteristics in a common base configuration. Apparatus: - BJT, ammeters, regulated power supply, breadboard, voltmeter, connection wires. Theory: - In his configuration, the base is made common to both the input and out.  A BJT is a three-terminal two junction semiconductor device in which the conduction is due to both the charge carrier. Hence, it is a bipolar device. BJT is classified into two types NPN or PNP. An NPN transistor consists of two N types in between which a layer of P is sand witched. The transistor consists of the three-terminal emitter, collector base. The emitter layer is the source of charge carrier and it is heavily doped with a moderate cross-sectional area.   The collector collects the charge carrier and hence moderate doping and large cross-section area. The base region acts as a path for the movement of the charge carrier. In order to reduce the recombination of holes and electrons the base region is lightly...

Purpose:- To study and plot the BJT characteristics in Common Emitter configuration. Theory: - A BJT is three terminal two junction semiconductor device in which the conduction is due to both the charge carrier. Hence, it is a bipolar device. BJT is classified into two types NPN or PNP.  A NPN transistor consists of two N types in between which a layer of P is sand witched. The transistor consists of three terminal emitter, collector base. The emitter layer is the source of charge carrier and it is heavily doped with a moderate cross sectional area.   The collector collects the charge carrier and hence moderate doping and large cross section area. The base region acts as path for the movement of the charge carrier. In order to reduce the recombination of holes and electrons the base region is lightly doped and is of low cross sectional are. BJT is operated in the active mode i.e emitter-base junction is forward biased and collector-base junction is reverse biased. It's Cu...

Purpose: - Study the characteristics of the Junction field-effect Transistor. Apparatus: - JFET, Power supply, ammeter, voltmeter, rheostat, connecting cables. Opinion: - The JFET or field-effect transistor is a final tool that uses an electric field to control the current flow through the device and has a high input impedance that is fully utilized in many circuits. Circuit Diagram:- Source: - It is the center where most carriers enter the bar. As the carriers come from it is called the source. Drain: - It is a facility where many carriers leave the bar i.e. they are removed from the area. The VDS voltage detection line drives the output ID Gate: - These are the two internal impurities that are connected internally that form the two PN channels. The voltage of the gate-source VGS reversing reverses the gates. Channels: - It is a space between two gates where most carriers pass from the source to the water where the V N-Channel JFET: - when we look at the silicon bar and form an N-edge...

Purpose: - Study the features and determine the Zener dynamics breakdown Apparatus: - Diener diode, ammeter, Resistor, voltmeter, breadboard, wires Circuit Diagram:-   Opinion: - A dot-shaped crystalline diode with a strong anti-depressant effect is known as the Zener diode. The Zener Diode has a set bias value that is used repeatedly in the drop down mode. There are two types of fractures. 1. Avalanche effect: - The avalanche fall controls on a simple doped Zener diode that is Vz above 6V. 2. Zener effect: - This effect is particularly important for high-voltage diodes with a Vz below 6V. Usually the PN junction of the Zener diode is heavily doped. Due to excessive impurity use the depletion layer will be smaller. When recurrent recurrence increases the potential for the entire deterioration layer is higher. This is stronger than the electron in the outer shell. Because of this energy, electrons are released from the parent nuclei and become free electrons. This ionization, w...

Purpose:- Determining the semiconductor power gap provided. Apparatus:- DC source, Milli-ammeter, Voltmeter, PN diode, connecting cables. Circuit diagram:- Opinion:- The semiconductor diode has a power space. It can be successfully measured in the case of reverse currents as only a small amount of current flow of small flow. Measured by eV unit. (1ev is equal to (1.602 × 1019) .The power gap between the top of the valence band and the bottom of the drive belt is called the bandgap. It is about 0.7V Germanium and 1.1 for Silicon. Process: - 1. Connect the circuit as shown in fig. 2. Immerse the PN junction diode in a paraffin test tube full of paraffin. 3. Start heating the bathwater and note that the temperature reaches 70C 4. Place the thermometer in the water bath and record the temperature. 5. As the temperature drops in all 50 records of current falls and electrical power up to room temperature. 6. The graph of the plot of logIs v / s (1000 / T) and determine the line drop. Tabular...

Purpose:- To study the forward and reverse bias characteristics of a given P-N junction diode and calculate forward reverse resistance, and Knee voltage. Apparatus:- Semiconductor Diode, Voltmeter, Milli-ammeter, DC source and connecting wires, breadboard. Principle:-   A semiconductor diode conducts electric current in forward bias mode and no significant current in reverse bias state .hence its resistance is low in forward bias and high in reverse bias. Circuit diagram:- Theory:- A semiconductor diode is a two-terminal P-N junction device. In forward bias state positive terminal of the external source is connected to P-type & negative to N-type & reverse bias vice versa. Knee voltage:- It is that forward voltage from which currently starts increasing. Dynamic resistance (rd):- it is the resistance of the P-N diode in forward bias mode. Break down voltage:- It is that reverse voltage at which sudden heavy current flows & a P-N  mode must not be operated at this vo...

Purpose: - Study the variability of semiconductor temperatures. Apparatus:- DC source, milli-ammeter, voltmeter PN diode, thermometer, beaker, electric heater, connecting cables. Theory:- A semiconductor is a temperature-sensitive device with a negative coefficient of temperature resistance.it is because the valence electron jumps into the conduction state. Process: - 1. The connection is made as shown in the picture. 2. Set a permanent DC source. 3. Heat water to 80 degrees 4. In every 5 falls 5. Plot graph of R v / s T & log R v / s 1 / T. Tabular column:- α = -2.303 × logR1-logR2 / T2-T1 Result: - Note that as the temperature increases resistance decreases. Value of temperature co-efficient is ____