Category: Physics Notes PPT

In electrostatics, the concept of Electric field and electric potential plays an important role. Electric field or electric field intensity is the force experienced by a unit positive test charge and is denoted by E. Electric potential is the work done to move unit charge against the electric field or the electric potential difference is the work done by conservative forces to move a unit positive charge and is denoted by V.

Mathematically, the electric field and the potential is given by:

⇒[E=frac{F}{q}]

⇒[V=frac{Kq}{r}]

The relation between electric field and potential is similar to that of the relation between gravitational potential and the field. The relation between Electric field and Potential is generally given by -the electric field is the negative gradient of the electric potential.

Relation between Electric Field and Potential

The relation between electric field intensity and electric potential can be found with a small derivation given below. To establish the relation between Electric field and electric potential we will use basic concepts of electrostatics.

Derivation

To derive a relation between electric field and potential, consider two equipotential surfaces separated by a distance dx, let V be the potential on surface 1 and V-dV be the potential on surface 2. Let E be the electric field and the direction of the electric field is perpendicular to the equipotential surfaces.

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Let us consider a unit positive charge +1C near point B, the force experienced by the unit positive charge is given by:

⇒ F= qE ……(1)

Since q= +1C, equation (1) becomes,

⇒F = E………..(2)

Equation (2) is indicating that the magnitude and the direction of the electric field and the force are equal, which means the direction of force is also perpendicular to the equipotential surfaces.

If we move the charge from point B to point A, the work done in bringing the charge from point B to point A is given by,

 ⇒WBA = F.dx

 ⇒WBA = F dx Cosθ ……(3)

From equation (2) F = E, Substituting the value of F in equation (3) we get,

 ⇒WBA = E dx Cosθ …….(4)

Now, the force experienced is acting in the upward direction, but the displacement is in the downward direction, thus the angle between force and displacement is 180°. 

Therefore, the work done in bringing the point charge from point B to A is given by:

 ⇒WBA = ─ E dx……….(5)

From the definition of electric potential, we know that the electric potential is the work done in bringing a point charge from one point to another, thus we have:

⇒ WBA = VA– VB

Substituting the corresponding values of the potential at point A and B,

⇒WBA = V- (V-dV)=dV …………..(6)

Equating equation (5) and (6):

⇒ dV =  ─ E dx

⇒E=−dV/dx………………(7)

Therefore, the relationship between field and potential is the electric field due to a point charge is negative potential gradient due to the point charge. Equation (7) is known as the electric field and potential relation.

Equation (7) is the relation between electric field and potential difference in the differential form, the integral form is given by:

We have, change in electric potential over a small displacement dx is:

⇒ dV =  ─ E dx

⇒ [int dV =  -int E.dx]

⇒ΔV= VA-VB = [- int E.dx]……..(8)

Equation (8) gives the integral form of a relation between the electric field and potential difference.

Case 1:

If the test charge is positive, then from the relationship between the electric field and electric potential, the potential gradient will be more near the charge.

Case 2:

If the test charge is negative, the potential gradient will be more as we move away from the test charge.

Case 3:

For an equipotential surface, the potential at every point on the surface will be the same, thus the potential gradient will be zero. The electric potential will be perpendicular to the electric field lines.

 

Examples:

1. Calculate the Electric Potential Due to a Point Charge at a Distance x From it.

Ans:

Given that, a point charge is placed at a distance x from point P(say). We are asked to calculate the potential at point P.

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We know that the electric field due to point charge is given by,

⇒[E = frac{kQ}{x^{2}}]

From the relation between the electric field and the potential we have,

⇒ [int dV = – int E.dx]

 The limit of integration for LHS is 0 to V and for RHS infinity to x.

Substituting the value of E in the above expression,

⇒[V^{v}0 = -int (frac{Kq}{x^{2}}).dx]

⇒[V= -Kq int x^{2}.dx]

On simplification we get,

⇒[V = frac{Kq}{x}]

Therefore, by using the relation between the electric field and the potential it is convenient to derive results. The same relation can be derived by using the definition of electric potential.

2. The Electric Potential V at Any Point X, Y, and Z in Space is Given by V=3x2 Volts, then the Electric Field at Any Point (2,1,2) is?

Ans: 

Given, the potential at any point x,y, and z,

⇒ V=3x2

We have to find the electric field E at (2,1,2).

We know that,

⇒[E=-frac{dV}{dx}]

⇒[E=frac{-d(3x^{2})}{dx}=6x]

At x=2,

⇒ E=6(2)=12 V/m

Therefore, the electric field E at (2,1,2) is 12V/m.

Electricity Keeping us Alive

Everyone is familiar with electricity in modern times.

We get electricity from sockets in walls in our houses. It gives us a shock if we touch it.

Science has taught us that all matter is made up of very small particles called atoms. These atoms are made of two kinds of charge – positive and negative. The middle part of the atom contains the positive charge and flying around this is the negative charge. Most of the time the number of positive and negative charges in an atom are equal in number – they exist in pairs. When they are not equal in number, the extra negative charge leaves the atom and goes looking for its partner. These stray charges are electrons and are easier to move about. These moving electrons make up electricity.

Types of Electricity

Electricity is of two kinds – static and current. Static electricity, electrons are moved mechanically. In current electricity, the electrons move in a closed loop. When the loop is broken, electr
icity cannot flow.

Lightning is static electricity. During thunderstorms, a cloud can develop a buildup of negatively charged particles. Electrons repel each other – they are always looking for positively charged particles to pair up with. So, they try to get away from other electrons and make a leap to the biggest thing nearby – the earth. Lightening is a big spark, a group of electrons that jumped to the earth to find their positively charged mate. Lightning is the biggest spark that exists; a lightning bolt has over 20 million volts.

The electric circuit is like the blood circulation system in a body. Blood is pumped in the arteries by the heart and then comes back to the heart having traveled through arteries and veins. In an electric circuit, electric charges are the blood and the wires are the arteries and veins. Electric charges have a little amount of energy. It is measured in Volt. A handheld flashlight has 1.5 Volt. The wall socket at home has 120 Volts. When electrons move through this circuit, trying to move away from the negative charge towards the positive charge, this flow forms the current. In the flashlight, we use batteries with a plus sign on one side and a minus sign on the other side. The plus sign side of the battery is where the extra positive charges are present. The other side with the minus sign stores the extra negative charge – the free electrons. Given a path, they are ready to run to find their pair. When we press the button of a flashlight, the loop is completed, and the circuit becomes complete. The electrons find their path and race out of the battery to the positive charges. The bulb forms a part of their path – the circuit. On their way, they make the wire inside the bulb very hot and it glows.

Similarly, when we touch the wall socket, lots of electrons (the electric current) flow through our body and this is why we get the shock.

Uses of Electricity in Daily Life

• The electrical field is used to push electrons through wires. This electricity powers the fans in our houses, the air conditioner, the computer, the charging sockets, and even the internet. 

• Electromagnetic waves use electric fields. This allows us to receive radio signals in cars and houses. This is also how we communicate via satellites, get weather information. 

• Since light is also an electromagnetic wave, the electric field helps us see in darkness. Everyday machines use electrical fields like motors and generators and the television. Without electrical fields, we would have no electricity. 

• Cars and airplanes use alternators and magnetos inside them that work through electricity. 

• The electric field also shields us from cosmic radiation and practically, we would all be dead without electric fields and electricity.

The law of conservation of mass is a very important concept, it says that we cannot create or destroy the mass; however, this mass can be transformed into another form.

In Physics, we express the law of conservation of mass as the differential form by continuity equation of the mechanics of fluids and continuum mechanics with the following equation:

∂ρ/∂t +⛛(ρv) = 0

Where,

ρ = density

t = time

v = velocity

⛛ = divergence

The law of conservation of mass states that in all the physical and chemical processes, the total mass of products in a chemical reaction is equal to the mass of reactants.

What is the Law of Conservation of Mass?

The Law of conservation of mass was studied by a French Chemist named Antoine Lavoisier in 1789.

This law states that in a chemical reaction, the mass of products in chemical reactions equals the mass of reactants.

According to this law, the matter cannot be created nor be destroyed. We call this law the law of indestructibility of matter. Let’s study the following experiments as the law of conservation of mass examples to get clarity in the conservation of mass definition:

When Matter Undergoes a Physical Change

Take a piece of ice (ice is solid water) and place it in a conical flask. This flask is properly corked and weighted and it is now heated gently to melt the ice into water.

Ice      → Heat    → Water

(solid)                    (Liquid)

The flask is weighed again, we notice that the weight of the flask remains the same because the mass of ice does not change after it undergoes a physical change.

When Matter Undergoes a Chemical Change

A Swiss Chemist named Hans Heinrich Landolt took two test tubes joined with a common line as shown below:

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One tube contains a solution of sodium chloride and another contains a silver nitrate solution; the tube containing these two solutions is called Landolt’s tube.

Both tubes were corked and weighed. Now, the above arrangement is tilted to let these solutions mix. The chemical reaction occurs, resulting in a curdy white precipitate of silver chloride. The reaction is as follows:

Nacl (s)          +        AgNO₃ (aqueous)       →         AgCl (s)            +     NaNO₃ (aqueous)

Sodium chloride           Silver Nitrate                   Silver Chloride            Sodium Nitrate

                                                                               (White precipitate)

After this reaction, the above arrangement was weighed again, it was found that the weight remains the same.

Decomposition of Mercuric Oxide (HgO)

When 100 g of HgO is heated,  it decomposes into two compounds viz: one mole of Hg and a half mole of O₂. The reaction occurs in the following manner:

HgO (s)                 →  Hg (l)       +       ½ O₂

Mercuric Oxide         Mercury         Oxygen 

      100 g                       92.6 g             7.4 g

Here, if we calculate the mass of products viz: Hg and O₂, i.e., 92.6 + 7.4 = 100g, which is equivalent to the mass of the reactant, i.e., HgO. So, the law of conservation of mass verifies here.

Combustion Process

When we burn pieces of wood, these pieces turn to ashes, water vapor, and carbon dioxide. 

If we weigh the piece of wood and after burning it, ashes, water vapors, and CO₂ are heated, there will not be any change in the mass before and after the reaction.

Now, let’s look at some more examples of the law of conservation of mass:

Law of Conservation of Mass Examples

Example 1:

Take a container and place 16 g of methane or CH₄ and 64 g of O₂. After the container is closed, CH₄ and O₂ remain closely packed. Now, ad the reaction proceeds, i.e., the combustion reaction, we get the following products:

CH₄ (gas)           +       2 O₂ (g)        →       CO₂ (g)            +    2 H₂ O (g)

Methane                     Oxygen               Carbon Dioxide          Water vapor

16 g                   64 g           44 g

Here, before the reaction, the total mass of reactants was:  

16 + 64 = 80 g

So, here what do you expect could be the mass of water vapor after the reaction?

Well, by the law of conservation of mass, the total mass of products must be 80 g. 

44 +  mass of H₂O = 80 g.

So, we get the mass of 2 moles of H₂O as 36 g.

Therefore, our final balanced equation after applying the principle of conservation of mass is:

CH₄ (gas)          +     2 O₂ (g)         →       CO₂ (g)           +    2 H₂O (g)

Methane                Oxygen                  Carbon Dioxide     Water vapor

16 g                           64 g                            44 g                        36 g

From here, we conclude that the sum of masses of reactants and products remain constant.

Example 2:

Take 10 g of CaCO₃. Now, after the decomposition, CaCO₃ decomposes to 6.2 g of CaO and 3.8 g of CO₂. So, let’s represent this equivalence of mass as the conservation of mass:

CaCO₃                     — decomposition →     CaO              +      CO₂

Calcium Carbonate                                 Calcium Oxide      Carbon dioxide

          10 g                                                          6.2 g                        3.8 g

Everything which we see happening around us is because of light. A particular frequency of electromagnetic radiation (which is also being referred to as light), which is around 390 to 700 NM, is visible to the eyes of the human. Even if we look at any particular leaf, we already know that it is green in colour because there is a light that bounces off the leaf to our eyes and tells us that it is green in colour. Light is any form of energy, just like all other energies, which is produced from a source. These sources are called light sources.

Types of Light Sources

In reality, we have a lot of sources of light, but all of them can be categorised under two categories which are known as natural sources and artificial sources. 

Natural Light Sources

In our universe, there are a lot of objects that emit light of their own. Some of the lights from these sources can reach the surface of the earth. The things which are present in nature and have the ability of emitting lights are given below.

• The Sun is one of the major sources of light for our planet Earth. The Sun is considered as a massive ball of fire that produces massive energy by the nuclear fusion at its centre. This energy from the Sun comes out in the form of light and heat. The major factor which is behind the sustainability of life on the planet Earth is the light from the Sun.

• Every star also produces light, but because of the huge distance between the Earth and these stars, only a small amount or sometimes no amount of it reaches the surface of the earth.

• The moon also provides light, but it doesn’t produce light of its own. The light which we get from the moon is the light that is being reflected by the moon from the Sun.

• Certain natural phenomenons also emit light, such as volcanic eruptions and lightning.

• There are some living organisms also who can produce light of their own. They are called bioluminescence. Some examples of these are jellyfish, fireflies, glow worms, etc.

Artificial Light Sources

Light can also be produced artificially apart from natural sources. The different lights which can be produced artificially come under three categories. Those categories include incandescent sources, luminescent sources and gas discharge sources.

Under incandescent sources, certain objects are being heated to a high temperature till they begin to emit light. In this process, both infrared and visible lights are being produced. Examples of incandescent sources are incandescent lamps and candles. An incandescent light source is the most common type of source in which Sun, light bulbs and fires can be included. Incandescent light is a type of light source which includes the vibration in the entire atom, as when the atoms are heated, then the thermal vibrations in the form of electromagnetic radiations are released. Depending on the temperature, the materials vary in emitting energy; at a low temperature of the materials, the emission of radiation takes place through infrared wavelengths in the photons. A common example of the incandescent light source is when a metal is heated, the atoms present in the metals gets vibrated and emit photons which emit radiation to make it visible to the human eye by raising the wavelength in the spectrum.

• Fire is the most common example of incandescent light, as fire includes a chemical reaction that releases both gases and heat, causing the material to reach a high temperature, causing the material and gases to be incandescent (lighten up). 

• Similarly, light bulbs produce heat through which electrical current passes, raising the temperature of the cable and finally providing incandescent to the cable. 

• Luminescent sources:

Under luminescent sources, lights are being produced by accelerating changes in the material of luminescence. The common way of doing this is bypassing the current through the material. Its examples are electric bulbs and fluorescent tube lights. As compared to incandescent light sources, these types of sources involve only electrons instead of the whole material vibrations, which takes place in normal or lower temperatures making it different from the Incandescent type of sources. Basically, we can say that when the electrons emit some part of their energy in the form of electromagnetic radiation, then the type of light is known as luminescence light. When an electron drops down in temperature, then the specific light colour is produced through the energy level decrement. Some common examples of Luminescence light sources are neon lights, fluorescent light, bioluminescence, fluorescence light, etc. Fluorescence light is the most common example of luminescence light source, which can be further divided into two parts which are electro-luminescence and photo-luminescence, which can include computers, screens and televisions. Bioluminescence is also the most common example of luminescence which even includes animals like fireflies. 

Under gas discharge sources, the electricity is being passed through a certain gas at very low pressure for producing light. Its examples include sodium lamps and neon lamps.

More About the Topic

There would be no world if lights were not there, as light provides us with the ability to see things. Plants also need light which is provided by the Sun in the form of sunlight through which many processes in nature take place, so we can say that the main source of light on earth is sunlight. Light comes from different sources, which are known as light sources, and these light sources can be defined as the sources through which light (a form of energy) is produced. Light is an energy source that can travel as a wavelength and can travel very quickly. Rainbow formed in the air is the very common example of light striking the droplets of water to separate colours with different wavelengths, making our eyes see those different wavelength colours forming the rainbow. We can say that light is a form of electromagnetic radiation whose particular particle can produce radiation of around 390 – 700 nm, which is visible to a human eye. The human eye can see almost all types of light except for infrared and ultraviolet rays. Our brain further processes the light captured by our eyes, translating the energy bandwidth into the colour spectrum our brain and eyes are sensitive to. The artificial life created by humans is formed by the movement of molecules (rational as well as vibrational) having the transitions with molecules or atoms. An atom or molecule gets excited and enters a state which is considered absorbing, while it can be said as entering an emitting state when these atoms or molecules relax. If the light is in any other form of electrical energy, then these electrical energies can be easily converted into light energy.

Basically, we can say that by exciting energy with any means necessary at that particular region, then it is said to be light, as the light lies in the visible spectrum in the form of energy or wave. In the modern world, humans are also creating arti
ficial light, which is the most suitable form of electrical energy in the current world. Neon lights, light bulbs and fluorescent tubes are very good examples of electrical light. Lasers are also a good example of artificial light.

Difference Between Natural Light and Artificial Light

The most important difference between natural light and artificial light is that natural light can be found in nature, but artificial light is electronic, which is formed with the help of advanced technology. Natural light has no control over the usage as it is based on the duration of time, but this is not in the case of artificial light. Usage of artificial light is limited. The amount of light produced is the main factor of using artificial light. If the artificial light is produced in less quantity, then the consumption is also low.

Lorentz Force Formula

The study of the magnetic fields is done by comparing the effects of electric fields with the effect of magnetic fields. Whenever we study the magnetic field we should keep in mind that the magnetic field is associated with moving charges, which means all the fields, forces that we derived for a point charge in a static condition will not be in good agreement with the charge considered in a magnetic field.

Charge under motion will result in current, then in order to derive the force acting on the moving charge, we will analyze the magnetic effect on electric current and hence derive the Lorentz force Formula.

Lorentz Law

We know that every charge experiences force when it is under the effect of either electric field or magnetic field. Dutch physicist Hendrik Antoon Lorentz, in the year 1895, formulated the formula for force giving rise to both electric and magnetic field effects. 

What is Lorentz Force Law? Define Lorentz Force:

Lorentz Force law is defined as the combined force experienced by a point charge due to both electric and magnetic fields. 

According to the Lorentz force definition, the Lorentz forces are the forces on moving charges due to the electromagnetic fields. The Lorentz force equation is given by small derivation.

Explain Lorentz Force

Consider a charge q moving with velocity v and it is moving in the existence of both electric and magnetic fields. Then we write:

The force due to the electric field is given by = F[_{E}] = qE

The force due to the magnetic field is given by = F[_{B}] = q(v х B)

Where,

q – Charge on particle under observation

E – Electric field due to point charge

v – Velocity of moving charges

B – The magnetic field due to moving charges

Now, Formula of Lorentz force is given by,

⇒F[_{L}] = F[_{E}] + F[_{B}]  

⇒F[_{L}] = qE + q(v х B)

⇒F[_{L}] = q{E + (v х B)} ………..(1)

Equation (1) is known as the Lorentz force equation. The direction of Lorentz force is perpendicular to the direction of the moving charge and the magnetic field. The Lorentz force direction is well explained by using the Right-hand rule (Lorentz Force right-hand rule).

Properties of Lorentz Force:

Case 1:

If the Electric field, magnetic field, and the direction of the velocity of the particle are parallel to each other and E and B are uniform,

then, F[_{B}] = qv sin 0 = 0 

Therefore, the charge will perform the rectilinear motion, because the charge will be accelerated due to the electric field.

Case 2:

If the Electric field and magnetic field are parallel to each other, and the direction of the velocity of the particle is perpendicular to  E and B, 

then, F[_{B}] ≠ 0

Therefore, the charge will perform the circular motion, because the charge will be accelerated due to the electric field.

Example:

1: What Should be the Velocity of a Charged Particle so that it will Not Experience Any Force or it will Not be Accelerated?

Ans: 

For a charged particle to remain unaccelerated, it must satisfy the condition that electrostatic force and magnetic force are equal.

⇒ for a = 0, Then, F[_{E}] = F[_{B}]  

Then,

⇒ F[_{E}] = F[_{B}]  

⇒ qE = q(v х B)  

⇒ E = vB sinθ

The angle between the magnetic field and the velocity of the charged particle is 90⁰.

Then,

⇒ E = vB

⇒ v = [frac{E}{B}]

Therefore, for the charged particle to remain accelerated the velocity of the charge must be equal to the ratio of the magnitude of the Electric and magnetic field.

Did You Know?

Lorentz force explains the importance of the effects of force acting on a charged particle. The right-hand rule is easy to calculate the magnetic force as the direction of the force can be visualized and demonstrated given by Lorentz force law.

What is Magnetic Declination?

Magnetic declination can be defined as the angle on the horizontal plane between magnetic and true north. This isn’t consistent and keeps on changing relying upon the situation upon the world’s surface and time. The Greek letter δ is recognized as the magnetic declination symbol and is otherwise called magnetic variation. 

The declination will be positive when the magnetic north is east of true north, and the declination will be negative when the magnetic north is west of true north. Different terms utilized are isogonic lines (when the lines along the declination are consistent) and agonic lines (when the lines along the declination are zero) 

Intrigued to learn more ideas identified with the magnetic field, have a look at more ideas underneath: 

• Electromagnetic Induction 

• Magnetic Flux 

• Magnetic Field and Magnetic Field Lines 

• Magnetic Poles and Their Significance 

There are three kinds of the north: True north, Grid north, and Magnetic north.

What is True North? 

True north can be defined as the direction towards the true north or the geological North Pole along the earth’s surface. It is otherwise called geodetic north and is not the same as the magnetic north which is the direction pointed by the compass and from the grid north which is toward the path along the grid lines towards the north. 

What is Grid North? 

Grid north can be defined as the direction which is in northwards along the grid lines on a map projection. This term is utilized for route and the deviation of the grid north from the true north is less. 

What is Magnetic North? 

Magnetic north can be defined as the direction which is pointed by the compass needle in light of the earth’s magnetic field. The deviation between the true north and the magnetic north differs from one to another as the earth’s magnetic poles are not fixed as for its axis. 

Contrast Between Magnetic North and True North 

Following is the table clarifying magnetic north versus true north: 

Magnetic North: It is pointed by the compass needle in the north direction which is along the earth’s magnetic field.

True North: It is the topographical north pointing towards the North Pole. 

What is Magnetic Dip? 

The magnetic dip can be defined as the edge by the earth’s magnetic field lines made with the horizontal. It is otherwise called dip angle or magnetic inclination and was found by Georg Hartmann in the year 1544. At the point when the inclination is positive, it shows that the earth’s magnetic lines are pointing downward in the northern half of the globe and when the inclination is negative it demonstrates that the earth’s magnetic lines are facing upward in the southern side of the equator. 

In the year 1581, Robert Norman found a dip circle which is a technique to estimate the dip angle. Different terms utilized are isoclinic lines (when the contour lines are equivalent at the earth’s surface) and aclinic lines (when the locus of the points are having zero dips). 

How to Calculate Magnetic Declination? 

From the declination calculator: The declination calculator is a simple method to figure the declination of any location on the earth. By giving the year, scope, and longitude of a given area, the calculator gives the declination based on magnetic reference field models. 

From a magnetic declination chart: A magnetic declination chart is a guide with the earth’s magnetic fields accessible on it. 

From a compass: There are three kinds of bearing, they are true, magnetic, and compass bearing. A compass can be utilized to figure the declination as it is one of the mistakes of the compass and the other is magnetic variation. These three are connected by: 

T = M + V 

M = C + D 

T = C + V + D (which is a general condition relating compass and true direction) 

Where, 

C is the compass bearing 

M is the magnetic bearing 

T is the true bearing 

V is the variation

D is the compass deviation 

V < 0, D < 0: this represents westerly variation and deviation 

V > 0, D > 0: this represents easterly variation and deviation 

Following is the best approach to compute compass bearing from true bearing: 

True bearing – variation = magnetic bearing 

Magnetic bearing – deviation = compass bearing 

Following is the best approach to compute true bearing from compass bearing: 

Compass bearing + deviation = magnetic bearing 

Magnetic bearing + variation = true bearing 

Presently it turns out to be evident that when we check for north direction utilizing a compass, the needle is really pointing towards the earth’s magnetic north and not the true north.

A sample of copper is magnetically drawn to the low field area to the right in the drawing, regardless of the orientation of the magnetic field. Diamagnetism is the name given to this type of behaviour.

A piece of aluminium, on the other hand, is drawn to the high field area by a phenomenon known as paramagnetism. Due to magnetization effects in matter, a dipole moment is created when the matter is subjected to an external field. Hence the degree of induced magnetization effects in matter is given by the magnetic susceptibility of the material χm, which is commonly defined by the equation

M = X_mH

The magnetic field H is called the magnetic intensity, like M, is measured in units of amperes per metre and X_m is denoted as the degree of induced magnetization.

For copper, the created dipole is opposite to the direction of the external field. Magnetic permeability is often used for ferromagnetic materials such as iron that have the largest magnetic susceptibility dependent on the magnetic field and the previous magnetic state of the sample. The magnetic permeability is defined by the equation,

B = μH.

The terms which are based on magnetization effects in matter are discussed in detail below.

Magnetic Field

A magnetic field is a vector field in the part of a magnetic material, electric current, or changing electric field, in which magnetic force is observable. Moving electric charges and intrinsic magnetic moments of elementary particles linked with a fundamental quantum property known as the spin create a magnetic field. The magnetic fields and electric fields are directly connected and are elements of the electromagnetic force, one of nature has four fundamental forces. A moving charge in a magnetic field has experienced a force perpendicular to its velocity and the magnetic field. The magnetic field of a permanent magnet draws or repels other magnets, as well as ferromagnetic materials such as iron.

A magnetic field surrounded by magnetized materials and is created by electric currents such as those used in electromagnetic fields, and by electric fields varying in time. 

A sample of copper is magnetically drawn to the low field area to the right in the drawing, regardless of the direction of the magnetic field. Hence is termed diamagnetism. A sample of aluminium is attracted toward the high field region is called paramagnetism.

A magnetic dipole is created when the matter is subjected to an external field. 

Magnetic Dipole

A dipole of an object generates a magnetic field in which the field is considered to emerge from two opposite poles, one is the north pole and the second is the south pole of a magnet, much as an electric field emerge from a positive charge and a negative charge in an electric dipole. 

The energy of a magnetic dipole is called the magnetic dipole moment. The amplitude of a uniform magnetic field is equal to the maximum amount of torque on the magnetic dipole, which happens while the dipole is at right angles to the field.

The magnetic dipole has a measurement of current times or energy divided by magnetic flux density. The magnetization M of a small volume of matter is the addition of the magnetic dipole in the small volume divided by that volume. 

Magnetic Flux

In physics, specifically magnetism, the magnetic flux is defined as the number of magnetic field lines passing through a given surface and magnetic field B over that surface. Hence, the area under consideration of any size and any orientation concerns the direction of the magnetic field. Magnetic flux is usually denoted by Φ or ΦB. The magnetic flux symbol is Φ or ΦB.

Magnetic flux formula is given by:

ϕ_B = B.A = BAcosθ

Where,

Magnetic flux is generally calculators with a flux meter. The SI unit and CGS unit of magnetic flux is given below:

Magnetic Intensity

The magnetic field to magnetization ratio of a material medium is called its magnetic intensity (H). Magnetic intensity of magnitude is calculated by the number of ampere-turns that flows around the unit length of a solenoid, required to produce that magnetic field.

Therefore, the magnetic intensity, due to a solenoid of n turns per meter length be H = ni, 

Where

i is the current

n = N/l, N is the total number of turns and l the size of the solenoid. 

Hence, the magnetic intensity does not depend upon the nature of the medium.

The SI unit of magnetic intensity (H) is ampere-turns per meter (Am⁻¹).

Magnetic Permeability

Magnetic permeability is described as the property of the material to accept the magnetic line of force to pass through it. In other words, the magnetic material can support the occurrence of the magnetic field. In (H) magnetic permeability of the magnetic line of force is directly proportional to the conductivity of the material. Magnetic permeability is the proportion of a material to respond to how much electromagnetic flux it can support to pass through itself within an applied electromagnetic field. In addition, the magnetic permeability of a material is the degree of magnetization capability.

Magnetic permeability is denoted by μ which is a Greek Letter. In 1885, Mathematician scientist Oliver Heaviside had termed magnetization effects as μ.

The SI unit is Henry per meter or newton per ampere-square.