Name: Khang Nguyen.Course:Phys2053.

I. Diode

Diode is electrical component with two electrodes called the anode and the cathode. Diodes are usually made with semi conductor material such as selenium or silicon. The fundamental property of a diode is its tendency to conduct electric current in only one direction.

First, a diode was connected to an AC power supply. This result in the negative half of the waves was block and therefore, only the positive half of the waves will go through. This process called half waves rectified voltage. The result is illustrated in graph 1.

Graph 1: Half waves rectified voltage.

Next, two diode was set parallel to each other and connected to a AC power supply. The first diode will keep the positive half of the waves. The second diode, however, will keep the negative half of the diodes and flip it up. The result of this is showed in the graph 2. This process called full waves rectified voltage.

Graph 2: Full waves rectified voltage.

II. Ohm’s law

Procedure

In this experiment, two resistor, one power supply and a multimeter are used. First of all, measure the resistance value of each resistor. Next, the experimenters connect the first resistor to the power supply and use multimeter to measure the current value (I). The experimenters change the current fives time and record down all current value.

Result

Resistor 1= 112.3 ohmResistor 2= 106.9 ohm

V

I (measured)

I (calculated)

2 0.02 0.0173 0.03 0.0356 0.05 0.0538 0.07 0.071

Table 1: Resistor 1’s current value with control Voltage

IV (measured)

V (calculated)

0.01 2 2.2460.03 3 3.3690.05 6 5.6150.07 8 7.861

Table 2: Resistor 1’s Voltage value with controlled current

V

I (measured)

I (calculated)

2 0.020.018709074

4 0.040.037418148

6 0.060.056127222

8 0.07 0.07483629

6Table 3: Resistor 2’s current value with control Voltage

IV (measure)

V (calculated)

0.02 2 2.1380.04 4 4.2760.06 6 6.4140.07 8 7.483

Table 4: Resistor 2’s Voltage value with controlled current.

0.01 0.02 0.03 0.04 0.05 0.06 0.07 0.080

1

2

3

4

5

6

7

8

9

MeasuredLinear (Measured)CalculatedLinear (Calculated)

Graph 3: Resistor 1’s current value with control Voltage

0 0.01 0.02 0.03 0.04 0.05 0.06 0.07 0.080

1

2

3

4

5

6

7

8

9

Measured Linear (Measured )CalculatedLinear (Calculated)

Graph 4: Resistor 1’s Voltage value with controlled current

0.01 0.02 0.03 0.04 0.05 0.06 0.07 0.080

1

2

3

4

5

6

7

8

9

Measured Linear (Measured )CalculatedLinear (Calculated)

Graph 5: Resistor 2’s current value with control Voltage

0.01 0.02 0.03 0.04 0.05 0.06 0.07 0.080

1

2

3

4

5

6

7

8

9

Measured Linear (Measured )CalculatedLinear (Calculated)

Graph 6: Resistor 2’s Voltage value with controlled current.

The different between measured and calculated values is small and can be justified. This is due to the experiment mistake or tool calibration.

III. Group Velocity