Apparatus:

Two solenoids, Constant current supply, Four probe, Digital gauss meter, Hall effect apparatus (which consist of Constant Current Generator (CCG), digital milli voltmeter and Hall probe).

Simulator controls

Combo box

Select procedure: This is used to select the part of the experiment to perform.

1. Magnetic field Vs Current.
2. Hall effect setup.

Select Material: This slider activate only if Hall Effect setup is selected. And this is used to select the material for finding Hall coefficient and carrier concentration.

Button

Insert Probe/ Remove Probe: This button used to insert/remove the probe in between the solenoid.
Show Voltage/ Current: This will activate only if Hall Effect setup selected and it used to display the Hall voltage/ current in the digital meter.
Reset: This button is used to repeat the experiment.

Slider

Current: This slider used to vary the current flowing through the Solenoid.
Hall Current: This slider used to change the hall current
Thickness: This slider used to change the thickness of the material selected.

Procedure for doing the simulation:

To measure the magnetic field generated in the solenoid

• Select Magnetic field Vs Current from the procedure combo-box.
• Click Insert Probe button
• Placing the probe in between the solenoid by clicking the wooden stand in the simulator.
• Using Current slider, varying the current through the solenoid and corresponding magnetic field is to be noted from Gauss meter.

Trial No	Current through solenoid	Magnetic field generated
1
2
3
4

Hall Effect apparatus

• Select Hall Effect Setup from the Select the procedure combo box.
• Click Insert Hall Probe button.
• Place the probe in between the solenoid by clicking the wooden stand in the simulator.
• Set "current slider" value to minimum.
• Select the material from the "Select Material" combo box.
• Select the Thickness of the material using the Thickness slider.
• Vary the Hall current using the Hall current slider.
• Note down the corresponding Hall voltage by clicking the "Show Voltage" button.
• Then calculate Hall coefficient and carrier concentration of that material using the equation.

$$R_H=V_Ht/(I\cdot B)$$

Where $R_H$ is the Hall coefficient

$$R_H=1/ne$$

And n is the carrier concentration

• Repeat the experiment with different magnetic file.

Trial No	Magnetic Field (Tesla T)	Thickness (t) m	Hall current (mA)	Hall Voltage (mV)	RH
1
2
3
4
5

Procedure for doing real lab

• Connect “Constant current source” to the solenoids.
• Four probe is connected to the Gauss meter and placed at the middle of the two solenoids.
• Switch ON the Gauss meter and Constant current source.
• Vary the current through the solenoid from 1A to 5A with the interval of 0.5A, and note the corresponding Gauss meter readings.
• Switch OFF the Gauss meter and constant current source and turn the knob of constant current source towards minimum current.
• Fix the Hall probe on a wooden stand. Connect green wires to Constant Current Generator and connect red wires to milli voltmeter in the Hall Effect apparatus.
• Replace the Four probe with Hall probe and place the sample material at the middle of the two solenoids.
• Switch ON the constant current source and CCG.
• Carefully increase the current I from CCG and measure the corresponding Hall voltage $V_H$ . Repeat this step for different magnetic field **B**.
• Thickness **t** of the sample is measured using screw gauge.
• Hence calculate the Hall coefficient $R_H$ using the equation 5.
• Then calculate the carrier concentration **n** using equation 6.

Result

Hall coefficient of the material = .........................

Carrier concentration of the material = ......................... m^-3