An engineer doesn’t want to scrap his very old vehicle and wants to use it for experiments. He makes an arrangement in such a way that the rear wheel of the vehicle stays between two strong parallel magnets. When he did the experiment, he noticed that when the rear wheel is rotating in between magnets, the conducting part of the wheel generates current in it. If the speed of the wheel is increased, then how will it affect the emf generated in the wheel? Obtain the expression of this energy which provides evidence of your answer.
Answers
Answer:
Here are answers to many common questions that people have about magnets and magnetism regarding the history, magnetic materials, magnetic properties, magnetic orientation, magnetic poles and more. For more technical info about these areas, visit our Magnetics-101-Design Guide.
1.0 History
2.0 The Basics
3.0 Magnetic Strength
4.0 Magnetic Field
5.0 Magnetic Poles
6.0 Magnetic Flux
7.0 Magnetic Orientation
8.0 Magnetic Characteristics
9.0 Magnetic Properties
10.0 Magnet Operating Temperatures
11.0 Machining Magnets
12.0 Magnetic Assemblies
13.0 Handling & Storage
14.0 Magnetic Resources
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1.0 A BRIEF HISTORY
The ancient Greeks and Chinese discovered that certain rare stones, called lodestones, were naturally magnetized. These stones could attract small pieces of iron in a seemingly magical way, and were found to always point in the same direction when allowed to swing freely, suspended by a piece of string, or floating on water. Early navigators used these magnets as rudimentary compasses to help them determine their direction while at sea.
The word "magnet" comes from Magnesia, a district in Thessaly, Greece where it is believed that the first lodestone was mined.
Over the years, magnets have evolved into the high-strength materials we have today. It was discovered that by creating alloys of various materials, one could create similar effects to those found in natural lodestone rocks, and increase the level of magnetism.
However, it was not until the 18th century that the first man-made magnets were created. Progress in creating stronger magnetic alloys was very slow until the 1920s when alnico magnet materials (an alloy of nickel, aluminum and cobalt) were formulated. Ferrite magnets were developed in the 1950s and rare-earth magnets in the 1970s. Since then, the science of magnetism has grown exponentially, and extremely powerful magnetic materials have made miniature and powerful devices possible. (top)
2.0 THE BASICS
What is a magnet?
Magnets can be made by placing a magnetic material, such as iron or steel, in a strong magnetic field. Permanent, temporary, and electromagnets can be produced in this manner.
The atoms forming materials that can be easily magnetized such as iron, steel, nickel, and cobalt are arranged in small units, called domains. Each domain, although microscopic in size, contains millions of billions of atoms and each domain acts like a small magnet. If a magnetic material is placed in a strong magnetic field, the individual domains, which normally point in all directions, will gradually swing around into the direction of the field. They also take over neighboring domains. When most of the domains are aligned to the field, the material becomes a magnet. (top)
Domains before magnetization
domains before magnetization
Domains after magnetization
domains after magnetization
What does a magnet do?
Magnets do the following things:
Attract certain materials, such as iron, nickel, cobalt, certain steels and other alloys.
Exert an attractive or repulsive force on other magnets (opposite poles attract, like poles repel).
Have an effect on electrical conductors when the magnet and conductor are moving in relation to each other.
Have an effect on the path taken by electrically charged particles traveling in free space.
Based on these effects, magnets transform energy from one form to another, without any permanent loss of their own energy. Examples of magnet functions are:
Mechanical to mechanical, such
Explanation:
The scenario given in question statement was first explained by Faraday and in physics this phenomena is recalled as Faraday's law of electromagnetic induction where a coil placed in placed field generates electricity when moved in the magnetic field. The generated Emf is directly proportional to the speed of movement
According to Faraday’s law, magnitude of induced e.m.f is,
E = dϕB/dt