V I Characteristics
This document was uploaded by user and they confirmed that they have the permission to share it. If you are author or own the copyright of this book, please report to us by using this DMCA report form. Report DMCA
Overview
Download & View V I Characteristics as PDF for free.
More details
- Words: 1,327
- Pages: 10
V-I Characteristics of a Wire, a Light Bulb and a Diode
Figure 1
Introduction In this experiment we measure the V-I characteristics of various electrical components. The measurements are done manually at first and then by automatic “scanning” of voltage using a sinusoidal voltage generator.
158
V-I Characteristics of a Wire, a Light Bulb and a Diode
Equipment •
Metal wire stretched on a ruler
•
Light bulb (3.5 V)
•
Diode.
•
1.5 V battery
•
1.5 V battery holder
•
Rheostat (∼15Ω)
•
Signal generator
•
MultiLogPRO or Nova or TriLink data logger
•
Voltage sensor ±2.5 V (or ±25 V)
•
Current sensor ±2.5 A
Equipment Setup Procedure 1.
Connect the data logger to the serial port of the computer
2.
Turn on the data logger
3.
Connect the Current sensor to the I/O 1 port of the data logger
4.
Connect the Voltage sensor to the I/O 2 port of the data logger
+ −
Wire
Current sensor
−
+
Voltage sensor To input 2 of MultiLog
+
To input 1 of MultiLog Figure 2
5.
Assemble the electric circuit as shown by figure 1: connect the rheostat as a potentiometer, connect the Current sensor and the metallic wire in series with the battery, then connect the Voltage sensor parallel to the wire. You can choose to work with one 1.5
V-I Characteristics of a Wire, a Light Bulb and a Diode
159
V battery or with three batteries according to the Voltage sensor available to you (See figures 1 and 2). 6.
Click Setup Wizard
on the main toolbar and program the
data logger according to the setup specified below
Initial Data Logger Setup Sensors: Input 1:
Current ± 2.5A
Input 2:
Voltage ± 2.5V (or ±25V)
Rate: Manual Recording time: 10 samples
Experimental procedure 1.
Click Edit graph
on the graph toolbar
2.
Select Input 1: Current in the X-axis list and Input 2: Voltage in the Y-axis list, then click OK on the upper toolbar to begin recording data
3.
Click Run
4.
Collect the data manually: Click Run
on the upper toolbar
each time you wish to record a data sample.
Note to MultiLogPRO users:
You can also push the Enter
button on
MultiLogPRO to collect data manually. 5.
Place the sliding terminal of the rheostat in a low voltage position and record the first data sample
6.
Change the potential difference between the terminals of the wire, begin with lower values and gradually increase the voltage. After each change record the data. Do not measure currents higher than 2.5 A.
160
V-I Characteristics of a Wire, a Light Bulb and a Diode
Figure 3
7.
After logging ends, click Add to Project
on the graph
toolbar 8.
Save
9.
Remove the rheostat and replace the batteries with a signal
the project
generator (see figure 4 in the next page) 10.
Select a sinusoidal signal, frequency 0.3 Hz and make sure that the voltage output does not exceed the range of the sensor (you can check this as you start the experiment by verifying that the graph of the voltage has a sinusoidal form).
V-I Characteristics of a Wire, a Light Bulb and a Diode
161
Figure 4
11.
Program the data logger according to the setup specified below
Second Data Logger Setup Sensors: Input 1:
Current ± 2.5A
Input 2:
Voltage ± 2.5V (or ±25V)
Rate: 100 samples per second Recording time: 5s (500 samples)
162
V-I Characteristics of a Wire, a Light Bulb and a Diode
Experimental Procedure (continued) 1.
Click Run
on the upper toolbar to begin recording data
2.
After logging ends, click Add to Project
on the graph
toolbar MultiLab creates default names for each graph that you add to the project. To change the name click Edit graph
, enter a new name in the Graph title edit box, then click OK
3.
Save
the project
4.
Repeat the experiment with different lengths of wire. Record in your notebook the length of wire for each experiment. After each experiment click Add to Project click Save
5.
on the graph toolbar, then
to save the new experiment to the project
Replace the wire with a diode and repeat the experiment. Save the results.
6.
Replace the diode with the light bulb and repeat the experiment. Save the results.
Data Analysis 1. 1.a.
Analyze the results for the metallic wire: Display one of the wire characteristic graphs by double-click its icon in the Data Map
1.b.
Click Linear fit
on the main toolbar. The fit equation will
be displayed in the information bar at the bottom of the graph window. The value of the slope is the resistance of the wire. Record this value in your notebook 2.
Repeat this procedure with all lengths of the wire and use the Capture tool to create a graph of resistance vs. wire-length:
V-I Characteristics of a Wire, a Light Bulb and a Diode
163
2.a.
Click Table on the menu bar, then click Capture
2.b.
Click Insert manual column, enter title (e.g. Length) and unit, and then click OK
2.c.
Repeat step b for the resistance data
2.d.
Click OK
2.e.
Click the first cell in the capture table and enter your data. Use the arrow keys on the keyboard to move to other cells and fill the two columns on the graph toolbar
2.f.
Click Edit graph
2.g.
Select Capture 1: Length in the X-axis list and Capture 2: Resistance in the Y-axis list, then click OK
2.h. 3. 3.a.
Discuss the resulting graph Analyze the diode characteristics: Display diode characteristic graph by double-click its icon in the Data Map
3.b.
Use the edit graph tool to display a graph of both the diode’s current and voltage vs. time (see figures 5 and 6). Answer the following questions:
3.c.
What is the resistance of the diode in each voltage polarity?
3.d.
What is the meaning of the constant value of the voltage when the current is positive?
164
V-I Characteristics of a Wire, a Light Bulb and a Diode
Figure 5
Figure 6
4. 4.a.
Analyze the light bulb characteristics: Display the bulb characteristics graph by double-click its icon in the Data Map. Answer the following questions:
4.b.
Why isn’t the graph linear (see Figure 7)?
4.c.
What is the effect of heat on the bulb’ resistance?
4.d.
Try to explain why the graph looks like a loop
4.e.
What is the expected effect of increasing the frequency of the voltage source? Perform an experiment with higher frequency
V-I Characteristics of a Wire, a Light Bulb and a Diode
165
Figure 7
Further Suggestions 1.
By measuring the diameter of the wire you may calculate the resistance of the metal. You may want to compare different metals.
2.
You may want to perform the measurements of the V-I characteristic of the light bulb manually using batteries as your voltage source instead of the signal generator. Set up the data logger according to the initial setup, change the number of points to 20 and gradually change the voltage. Each time you change the voltage wait a few seconds for the bulb to reach steady state temperature and then click the Samples button. This V-I characteristic will give an indication of the expected behavior of the bulb in DC conditions.
3.
During the experiment with the light bulb you may use a Light sensor simultaneously with the Voltage and Current sensors.
166
V-I Characteristics of a Wire, a Light Bulb and a Diode
You can then compare the power output with the light intensity (see figure 8). To display a graph of the power: 3.a.
Click Analysis Wizard
on the main toolbar, then click the
Functions tab 3.b.
In the Functions drop list select Multiply
3.c.
In G1 drop list select the current and in G2 drop list select the voltage
3.d.
Click OK
Figure 8
V-I Characteristics of a Wire, a Light Bulb and a Diode
167
Figure 1
Introduction In this experiment we measure the V-I characteristics of various electrical components. The measurements are done manually at first and then by automatic “scanning” of voltage using a sinusoidal voltage generator.
158
V-I Characteristics of a Wire, a Light Bulb and a Diode
Equipment •
Metal wire stretched on a ruler
•
Light bulb (3.5 V)
•
Diode.
•
1.5 V battery
•
1.5 V battery holder
•
Rheostat (∼15Ω)
•
Signal generator
•
MultiLogPRO or Nova or TriLink data logger
•
Voltage sensor ±2.5 V (or ±25 V)
•
Current sensor ±2.5 A
Equipment Setup Procedure 1.
Connect the data logger to the serial port of the computer
2.
Turn on the data logger
3.
Connect the Current sensor to the I/O 1 port of the data logger
4.
Connect the Voltage sensor to the I/O 2 port of the data logger
+ −
Wire
Current sensor
−
+
Voltage sensor To input 2 of MultiLog
+
To input 1 of MultiLog Figure 2
5.
Assemble the electric circuit as shown by figure 1: connect the rheostat as a potentiometer, connect the Current sensor and the metallic wire in series with the battery, then connect the Voltage sensor parallel to the wire. You can choose to work with one 1.5
V-I Characteristics of a Wire, a Light Bulb and a Diode
159
V battery or with three batteries according to the Voltage sensor available to you (See figures 1 and 2). 6.
Click Setup Wizard
on the main toolbar and program the
data logger according to the setup specified below
Initial Data Logger Setup Sensors: Input 1:
Current ± 2.5A
Input 2:
Voltage ± 2.5V (or ±25V)
Rate: Manual Recording time: 10 samples
Experimental procedure 1.
Click Edit graph
on the graph toolbar
2.
Select Input 1: Current in the X-axis list and Input 2: Voltage in the Y-axis list, then click OK on the upper toolbar to begin recording data
3.
Click Run
4.
Collect the data manually: Click Run
on the upper toolbar
each time you wish to record a data sample.
Note to MultiLogPRO users:
You can also push the Enter
button on
MultiLogPRO to collect data manually. 5.
Place the sliding terminal of the rheostat in a low voltage position and record the first data sample
6.
Change the potential difference between the terminals of the wire, begin with lower values and gradually increase the voltage. After each change record the data. Do not measure currents higher than 2.5 A.
160
V-I Characteristics of a Wire, a Light Bulb and a Diode
Figure 3
7.
After logging ends, click Add to Project
on the graph
toolbar 8.
Save
9.
Remove the rheostat and replace the batteries with a signal
the project
generator (see figure 4 in the next page) 10.
Select a sinusoidal signal, frequency 0.3 Hz and make sure that the voltage output does not exceed the range of the sensor (you can check this as you start the experiment by verifying that the graph of the voltage has a sinusoidal form).
V-I Characteristics of a Wire, a Light Bulb and a Diode
161
Figure 4
11.
Program the data logger according to the setup specified below
Second Data Logger Setup Sensors: Input 1:
Current ± 2.5A
Input 2:
Voltage ± 2.5V (or ±25V)
Rate: 100 samples per second Recording time: 5s (500 samples)
162
V-I Characteristics of a Wire, a Light Bulb and a Diode
Experimental Procedure (continued) 1.
Click Run
on the upper toolbar to begin recording data
2.
After logging ends, click Add to Project
on the graph
toolbar MultiLab creates default names for each graph that you add to the project. To change the name click Edit graph
, enter a new name in the Graph title edit box, then click OK
3.
Save
the project
4.
Repeat the experiment with different lengths of wire. Record in your notebook the length of wire for each experiment. After each experiment click Add to Project click Save
5.
on the graph toolbar, then
to save the new experiment to the project
Replace the wire with a diode and repeat the experiment. Save the results.
6.
Replace the diode with the light bulb and repeat the experiment. Save the results.
Data Analysis 1. 1.a.
Analyze the results for the metallic wire: Display one of the wire characteristic graphs by double-click its icon in the Data Map
1.b.
Click Linear fit
on the main toolbar. The fit equation will
be displayed in the information bar at the bottom of the graph window. The value of the slope is the resistance of the wire. Record this value in your notebook 2.
Repeat this procedure with all lengths of the wire and use the Capture tool to create a graph of resistance vs. wire-length:
V-I Characteristics of a Wire, a Light Bulb and a Diode
163
2.a.
Click Table on the menu bar, then click Capture
2.b.
Click Insert manual column, enter title (e.g. Length) and unit, and then click OK
2.c.
Repeat step b for the resistance data
2.d.
Click OK
2.e.
Click the first cell in the capture table and enter your data. Use the arrow keys on the keyboard to move to other cells and fill the two columns on the graph toolbar
2.f.
Click Edit graph
2.g.
Select Capture 1: Length in the X-axis list and Capture 2: Resistance in the Y-axis list, then click OK
2.h. 3. 3.a.
Discuss the resulting graph Analyze the diode characteristics: Display diode characteristic graph by double-click its icon in the Data Map
3.b.
Use the edit graph tool to display a graph of both the diode’s current and voltage vs. time (see figures 5 and 6). Answer the following questions:
3.c.
What is the resistance of the diode in each voltage polarity?
3.d.
What is the meaning of the constant value of the voltage when the current is positive?
164
V-I Characteristics of a Wire, a Light Bulb and a Diode
Figure 5
Figure 6
4. 4.a.
Analyze the light bulb characteristics: Display the bulb characteristics graph by double-click its icon in the Data Map. Answer the following questions:
4.b.
Why isn’t the graph linear (see Figure 7)?
4.c.
What is the effect of heat on the bulb’ resistance?
4.d.
Try to explain why the graph looks like a loop
4.e.
What is the expected effect of increasing the frequency of the voltage source? Perform an experiment with higher frequency
V-I Characteristics of a Wire, a Light Bulb and a Diode
165
Figure 7
Further Suggestions 1.
By measuring the diameter of the wire you may calculate the resistance of the metal. You may want to compare different metals.
2.
You may want to perform the measurements of the V-I characteristic of the light bulb manually using batteries as your voltage source instead of the signal generator. Set up the data logger according to the initial setup, change the number of points to 20 and gradually change the voltage. Each time you change the voltage wait a few seconds for the bulb to reach steady state temperature and then click the Samples button. This V-I characteristic will give an indication of the expected behavior of the bulb in DC conditions.
3.
During the experiment with the light bulb you may use a Light sensor simultaneously with the Voltage and Current sensors.
166
V-I Characteristics of a Wire, a Light Bulb and a Diode
You can then compare the power output with the light intensity (see figure 8). To display a graph of the power: 3.a.
Click Analysis Wizard
on the main toolbar, then click the
Functions tab 3.b.
In the Functions drop list select Multiply
3.c.
In G1 drop list select the current and in G2 drop list select the voltage
3.d.
Click OK
Figure 8
V-I Characteristics of a Wire, a Light Bulb and a Diode
167
Related Documents
V I Characteristics
October 2019 5
Characteristics
June 2020 36
Characteristics
November 2019 50
:characteristics
June 2020 29
