ELECTROMAGNETISM
Magnetic Induction, Inductance, AC and LC Circuits
Enrichments
This section of the module will explore some practical applications of the lesson contained, some suggested activities or relevant reading list that would enhance student's knowledge and experience inside the classroom. It's up to the teacher how he/she would creatively integrate this to the lesson.
REAL-WORLD PHYSICS
The Physics of Electric Guitar
Electric Guitar pick ups uses the principle of electromagnetic induction. When the string is plucked or vibrated, emf is induced in the coil of the pickup which is then amplified and transmitted to the speakers
Schematic of Electric Guitar Pickup.
Kshitij Education India Private Limited (2015) Faraday's Law of Induction. Retrieved from http://www.kshitij-iitjee.com/Faraday%E2%80%99s-law-of-induction
An Electric Guitar
SUGGESTED ACTIVITY
The teacher can use this diagram to explain how the pick-up in the guitar works. If material is available, learners can explore the guitar itself to show it first-hand.
REAL-WORLD PHYSICS
The Physics of Ground Fault Interrupter
This is a safety device that uses Faraday's Law to prevent electrical appliance user from experiencing electric shock. Notice the two wires: the first wire leads from the outlet to the appliance while the second wire is the reverse of the first wire so that the net magnetic flux through the sensing coil is zero. In times of emergency when the return wire's current changes, meaning there has been leaked on the current to the ground, the induced magnetic flux through the coil is no longer zero, then that's the signal for the induced emf to alert the circuit breaker that would stop the current before creating a disastrous damage.
Schematic of Ground fault-Interrupter
Kshitij Education India Private Limited (2015) Faraday's Law of Induction . Retrieved from
http://www.kshitij-iitjee.com/Faraday%E2%80%99s-law-of-induction
SUGGESTED ACTIVITIES
1. The teacher can ask students to write an essay or reflection on the topic :"How has Faraday's law change the course of modern living and technology?"and present it to the class
2. Create an infographic on how the discovery of electromagnetism affected our lives today
REAL-WORLD PHYSICS
The Physics of Microphone
21ST CENTURY SKILL
Communication and Collaboration
Information and Media Literacy
When sound waves travel and strike the diaphragm of the microphone, the diaphragm vibrates and the coil also moves along with these vibrations. The coil is wound on a stationary magnet therefore changing the magnetic flux through the coil. In this process, an induced emf is created which is then sent as an electrical signal to the amplifier then to the speaker.
Schematic of Microphone.
Kshitij Education India Private Limited (2015) Faraday's Law of Induction. Retrieved from http://www.kshitij-iitjee.com/Faraday%E2%80%99s-law-of-induction
REAL-WORLD PHYSICS
The Physics of MRI
Magnetic Resonance Imaging more commonly known as MRI employs strong electromagnet and radio waves to see inside the body.The MRI scan provides more details than X-ray images in a non-invasive method by allowing electric current to flow in the solenoid.This process induces a strong magnetic field and once the body is exposed, the hydrogen atoms inside the body act like compasses and once current is removed, the atoms return to their original position. Simultaneously, the atoms release radiowaves that the machine detects and that allows the surgeons "see" inside the body.
An MRI commonly found in advanced hospitals.
Lester Lefkowitz/Photographer's Choice/Getty Images (2015)
Retrieved from http://science.howstuffworks.com/mri.htm
