ExpEYES/C2/Electro-Magnetism/English-timed
Time | Narration |
00:01 | Hello everyone. Welcome to this tutorial on Electro-magnetic induction. |
00:06 | In this tutorial, we will demonstrate:
Electro-magnetic induction Mutual induction of coils Voltage induced by a rotating magnet Resonance of driven pendulum and show circuit diagrams for our experiments. |
00:26 | Here, I am using:
ExpEYES version 3.1.0 Ubuntu Linux OS version 14.10 |
00:35 | To follow this tutorial, you should be familiar with ExpEYES Junior interface. If not, for relevant tutorials, please visit our website. |
00:47 | Let's begin with the demonstration of Electro-magnetic Induction. |
00:52 | In this experiment, wires of 3000 turns coil are connected to ground (GND) and A1. |
01:00 | To show the magnetic effect, a magnet with 5mm diameter and 10mm length is used.This is the circuit diagram. |
01:11 | Let's see the result on the Plot window. |
01:15 | A horizontal trace appears on the Plot window. Roll a paper and insert it inside the coil. |
01:23 | Drop the magnet inside the rolled paper and move it up and down. |
01:29 | Repeat the process until the induced voltage is captured and displayed. |
01:35 | On the Plot window, click on Experiments button. |
01:39 | Select Experiment list appears. Click on EM Induction. |
01:46 | Two new windows- Electromagnetic Induction and Schematic appear.
Schematic window shows the circuit diagram. |
01:56 | On the Electromagnetic Induction window, click on Start Scanning button. Horizontal trace changes to a wave. |
02:05 | It happens when the periodic scanning of the voltage coincides with the movement of the magnet. |
02:12 | This indicates that voltage is induced in the coil by a moving magnet. |
02:18 | Next, I will demonstrate mutual induction of two coils. |
02:23 | In this experiment, A2 is connected to SINE. SINE is connected to ground(GND) through a coil. |
02:31 | And A1 is connected to ground (GND) through a coil. This is the circuit diagram. |
02:37 | Let's see the result on the Plot window. |
02:40 | Click on A1 and drag to CH1. A1 is assigned to CH1. |
02:47 | Click on A2 and drag to CH2. A2 is assigned to CH2. |
02:55 | Move the msec/div slider to view the applied waveform and induced waveform. |
03:02 | A changing magnetic field causes induced voltage. You may not see any induced voltage on the secondary coil. |
03:12 | Keep the coils close to each other along the axis. Insert some ferromagnetic material along the axis. |
03:20 | We have inserted a screw driver to induce voltage on the secondary coil. |
03:26 | Click and drag CH1 to FIT. Click and drag CH2 to FIT. |
03:34 | Voltage and frequency of A1 and A2 are seen on the right.
Difference in the voltages of A1 and A2 is due to the induced voltage on the secondary coil. |
03:47 | Next, we will demonstrate voltage induced by a rotating magnet using DC motor and coils. |
03:56 | In this experiment,
A1 is connected to ground(GND) through a coil. SQR2 is connected to ground(GND) through a DC motor. |
04:06 | A permanent magnet of 10mm diameter and 10mm length is mounted on DC motor.
A2 is connected to ground (GND) through a coil. |
04:18 | This is the circuit diagram. |
04:20 | Let's see the result on the Plot window. |
04:23 | Under Setting Square waves, set the frequency value to 100Hz. Click on SQR2 check-box. |
04:34 | Click on A1 and drag to CH1. A1 is assigned to CH1. |
04:41 | Click on A2 and drag to CH2. A2 is assigned to CH2. |
04:47 | Move the msec/div slider to obtain the wave form.Move the volt/div slider to adjust the wave form. |
04:57 | Click on CH1 and drag to FIT.
Click on CH2 and drag to FIT. |
05:05 | On the right side, you can see voltage and frequency. Please note, voltage and frequency values of the two alternating waveforms are almost the same. |
05:16 | This is because, as the magnet rotates, magnetic field around the coil constantly changes between the poles. |
05:24 | Rotation of the magnet results in alternating induced emf in the coil. |
05:31 | Next, let's experiment with driven pendulum. |
05:34 | If a pendulum oscillates with an induced magnetic field, it is called a driven pendulum. |
05:41 | In this experiment, SQR1 is connected to Ground (GND) using a coil. |
05:47 | Button magnets are suspended in front of the coil with a paper strip as a pendulum. This is the circuit diagram. |
05:58 | Let's see the result on the Plot window. |
06:01 | click on SQR1 check box. |
06:05 | Click on Experiments button. Select Experiment list appears. Select Driven Pendulum. |
06:15 | Two windows appear-
Schematic of Driven Pendulum and EYES Junior: Driven Pendulum. |
06:23 | On the EYES Junior: Driven Pendulum window, drag the slider. As we drag the slider, the pendulum oscillates. |
06:33 | Between "2.6 Hz" to "2.9Hz" pendulum oscillates with a maximum amplitude.
This is because, its resonant frequency is same as its natural frequency. |
06:47 | Let's summarize. |
06:49 | In this tutorial, we have learnt to demonstrate:
Electromagnetic induction Mutual induction of coils Voltage induced by a rotating magnet Resonance of driven pendulum and show circuit diagrams for our experiments. |
07:09 | As an assignment, demonstrate:
How to make an electromagnet induction of a single coil with a magnet Show circuit diagrams for the experiments. |
07:22 | This video summarizes the Spoken Tutorial project.If you do not have good bandwidth, you can download and watch it. |
07:30 | We conduct workshops using Spoken Tutorials and give certificates. Please contact us. |
07:37 | The Spoken Tutorial Project is funded by NMEICT, MHRD, Government of India. |
07:44 | This tutorial is contributed by Kaushik Datta and Madhuri Ganapathi.Thank you for joining. |