L3 Physical Science Electromagnetism

ELECTROMAGNETISM Lecturer :Semase M.P Physicalfrom Downloaded Science L3 hlayiso.com Sefikeng Campus

Subject outcome State, analyse and apply principles electromagnetism Learning outcomes * Identify and draw diagrams of the magnetic field associated with current *Long straight current carrying conductor and in a solenoid. *Identify and describe the use of magnetic field and its application in electromagnets. * Identify the effect of the magnetic field on a charged particle vin motion. * Describe and apply electromagnetic induction to produce current by changing magnetic field and how it is applied in dynamos and transformers Downloaded from hlayiso.com

Introduction Electromagnetism is the study of forces between charged particles, electromagnetic fields, electric potentials, the behaviour of conductors and insulators in fields, magnetism and electromagnetic waves. Downloaded from hlayiso.com

Sections of electromagnetism (1) Magnetic fields (2)Electromagnetic and their applications induction Downloaded from hlayiso.com

Magnetic fields and their application • Magnetic field is a region close to a magnet in which a compass needle experiences a deflection Downloaded from hlayiso.com

Magnetic fields and their application Diagrams of Flemings Right hand magnetic Left hand rule field rule Downloaded from hlayiso.com

Using Right hand rule for finding direction of the magnetic field Direction of magnetic field around a straight conductor can be obtained by using the right hand rule: • Grasp the conductor in your right hand • Point thumb in the direction of the current • The curl ofDownloaded from your fingers gives hlayiso.com direction of the field

Using Right hand rule for finding polarity of the magnetic field polarity of magnetic field around a solenoid can be obtained by using the right hand rule: • Right hand rule gives us polarity of the magnetic field around solenoid • Curl fingers around the solenoid in the direction of Downloaded from hlayiso.com the current

Summary • We have learned about magnetic fields and their use • When a current flows through a conductor a magnetic filed exists around the conductor • A solenoid behaves like a magnet when a current flows through it Downloaded from hlayiso.com

Assessment activity 10.4 Page 110 1. Use books, the internet or any source available to you to research the use of electromagnets in industry. In your report include the following: • Electromagnets ( Telephones, loudspeakers) • Lifting magnets • Electric bell • Magnetic relays • Magnetic separators 2. Mention the construction of electromagnets and how they carry out the function mentioned. (15marks) Downloaded from hlayiso.com