Michael Faraday’s Homopolar Motor:
Research done by Zoe, Sowmya, and Bela
- Invented in 1821 (discovered right before electromagnetism) → Michael Faraday
- First electrical motor to be built
- Also known as unipolar motors
- Simpler structure, higher rotor strength, and lower iron loss in rotations
- Direct current (DC) and Low voltage
- Used in modern day plating, turbines, and toys.
- Plating: used in generators installed for electroplating process plants
- Has evolved to have high enough voltage to operate heavy machinery despite low power outage
- Turbines: used in high-torque wind turbines
- Provide low cost means of converting wind to electricity due to reduced need for multidirectional gears
- Require less maintenance than bipolar motors
- Toys: small engines in toy cars are an example of the homopolar motor
- Spinning wheel create force → magnet spins and creates electric field
- Electricity is flowing in one direction to power the car (the engine specifically)
- Plating: used in generators installed for electroplating process plants
- Can be inefficient due to counterflow of current, causing inefficiency of early homopolar motors
- Homopolar motor is driven by Lorentz Force → this force provides a torque around the axis of rotation (parallel to magnetic field)
- Powers motor in one direction
- Useful for demonstrating scientific forces such as electromagnetism
- Otherwise kind of useless due to high electrical currents, poor efficiency, and inability to get much useful power out of it
- Magnet and compass (deviating the needle) → do the same with copper wire and AA battery → demonstrate electromagnetism
“The magnet’s magnetic field pushes up towards the battery and the current that flows from the battery travels perpendicularly from the magnetic field. This causes the creation of a force perpendicular to both the magnetic field and current. This force, known as the Lorentz force, is exerted on the copper wire (the conductor) causing it to spin” (CSUB)
Questions:
- What’s the difference between a homopolar generator and a homopolar motor?
- Were homopolar motors the beginning of cars → possible relevance between modern cars and the motor?
- Can homopolar motors or even just remnants of it be found in everyday inventions? (pulleys → elevators)
Vocabulary:
Electromagnetism: the physical interaction among electric charges, magnetic moments, and the electromagnetic field
Torque: a twisting force that speaks to the engine’s rotational force and measures how much of that twisting force is available when an engine exerts itself
Lorentz Force: the force exerted on a charged particle q moving with velocity v through an electric field E and magnetic field B
Formula : F = q( E + vB)
F = force
q = electric charge
E = external electric field
vB = velocity times magnetic field
Do It Yourself (DIY) Homopolar Motor:
By Vanisha Nagali
*Use the link below for step by step instructions*