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Electromagnets and Electromagnetism - Coggle Diagram
Electromagnets and Electromagnetism
Applications
Electric Motors
Used in electric cars, such as the tesla induction motors
Magnetic Levitation
This is used for magnetic trains, such as the maglev in China, the benefits of maglev is that it minimises friction, increasing efficiency and speed
Magnetic Resonance Imaging
This is a medical imaging technique used to visualise the inside of the human body, such as the brain. MRI works based on the principles of nuclear magnetic resonance and the interaction with nuclei with a magnetic field.
Factors that effect its effectiveness
Number of loops around Electromagnet
Shape and thickness of coils
The thickness of the wire of the coils determines the resistivity of the wire, as resistivity is inversely proportional to cross sectional area
Current Flow (Amperage)
Temperature
The temperature of the wire around the conductor can cause resistance which can impact current flow
Physical Laws
Coloumbs Law
Describes electrostatic force between two point charges, which applies to electromagnetism
Faradays Law
Describes how a changing magnetic field induces an EMF, it also descriebs how a hollow conductor doesnt have an electric field inside of it
Ohms Law
Describes the relationship between voltage, current and resistance
Lenz Law
States the directinon of the electromotive force
How it works
They work by using electric current to generate a magnetic field. It consists of a coil of wire wound around a core material, typically made of iron or steel. When electric current flows through the coil, it creates a magnetic field around the electromagnet. The strength of the magnetic field depends on the amount of current flowing through the coil and the properties of the core material.
Functionality
Lifting and Holding
Controlling Magnetic Field
The benefit of electromagnets, unlike other magnets is its ability to disable and enable its magnetic field by switching the current on an of (as a current flow is required for an electromagnet to work) hence the name. The power can also be controlled by increasing any independent variable.
Magnetic Shielding
The shielding effect is based on faradays cage principle, electromagnets can be used to create a conductive barrier that completely surrounds a gadget or device to protect from external interference from electromagnetic fields.
Faradays Law
Dangers and precautions
Electric Shocks
Deailng with electricity makes electric shocks inevitable, make sure the correct safety equipment is worn and the correct procedures are followed
Heating and smoking
High current means that therer will be a lof heat generated, this can be reduced by lowering voltage if making a simple electromagnet, if smoke is seen make sure to turn the system off immediately
EMF interference
Can interfere with other electronic devices such as hard drives and laptops
Physics Equations
There are several equations which correlate electromagnetism, especially relating to factors which affect the strength of the magnetic field (these include many equations from electricy and magnetism)
Magnetic Field Strength inside a solenoid where μ = permeability, n = number of turns and I = Current in amps. B is always magnetic field strengh
Magnetic Field strength through a wire
Force on a charged Particle Formula
V = I*R or R = ρL/A for voltage and resistance
Limitations
Power Consumption
Electromagnets require a continous power supply to keep them running, and as magnetic fields often require higher power, it leads to increaed power consumption, and not being very energy efficient.
Portability
Many high power electromagnets have systems to keep it cool and maintained, making it extrememly hard to move and be integrated into other applications
Limited Range
The furher away an electromagnet is from its target, the lower the magnetic field strength will be and in order to increase the field strenth more power must be applied, this reduces the range electromagnets and more mechanical energy must be used in moving the electromagnet to its target, or its target closer to the electromagnet
