Lorentz force

Proof of Faraday's Law
It is evident from Faraday's experiments that whenever there is a change in the magnetic flux passing through a closed circuit, an electric current is induced in the circuit. It can be explained on the basis of Lorentz force.

Suppose a conducting-rod JK (Fig. 7) is being moved without friction on the arms of a U-shaped stationary conductor MNOL with a velocity v towards right. The conductor is situated in a magnetic field B perpendicular to the plane of paper directed downwards. Due to the motion of the conducting-rod, the free electrons present in the rod are acted upon by a magnetic (Lorentz) force F_m of magnitude qvB which takes the electrons from the end J of the rod to the end K. Since a closed circuit is available to the electrons, they drift along the path J-*K-*O^N-*J. Thus, an electric current is established in the circuit along J->N->0->K-*J (anticlockwise)*. So long the rod JK is kept moving in the magnetic field, the electric current continues to flow in the circuit. It means that an emf is induced in the moving rod which maintains the current in the circuit. Since this emf induced in the rod is due to the motion of the rod, it is also called as the 'motional emf. It is due to the Lorentz forces acting on the free electrons in the moving rod.

Suppose, the induced emf in the moving rod JK is e and the induced current in the circuit is i. We know that when a current-carrying conductor is in a magnetic field, it is acted upon by a force in a direction given by the Fleming's left-hand rule. The magnitude of the force imposed by the magnetic field B on the current-carrying rod JK is given by
F' = i IB,

where I is the length of the rod JK. The force F*' is directed towards left. Hence, to keep the rod moving with a constant velocity v towards right, a force F equal and opposite to F' will have to be applied on it; that is
F = -F' = -ilB.

Suppose, under the force Ft the rod JK undergoes a displacement Ax* in the direction of the force in a time-interval At and comes in the position J 'K'. Then, the work done on the rod will be given by
W =F*.Ax*= F Ax = -HB Ax. But A* = v x Af (magnitude of velocity x time-interval).
W = -HBvAt.
But i x At = q (charge flown through the circuit in time At)
W = -Bvlq.

This work provides the necessary energy for the flow of charge in the circuit. We know that the energy supplied by a cell in flowing unit charge through a circuit is called the emf of the cell. Hence the induced emf e in the rod / K (which is working as a cell in the circuit J N O K J) is given by
e = W/q = - Bv I. ...(i)

In the time-interval At, the area of the circuit increases from JNOKJ to J' N O K' JHence, during this time-interval, the change in the magnetic flux passing through the circuit is given by
A<P_b = magnitude of magnetic field x change in area (JJ 'K'K) = B x (I x Ax).

Hence the rate of change of magnetic flux is
AO_fl Ax
I — O I ~~ .
At At
But Ax/At = v (velocity of the rod). Thus
-tf'Blv. ...(ii)
Comparing eq. (i) and (ii), we get
A<D_fl
^{e =} -~AT■
In the limit At —» 0,
d<b_B
^{e =} ~~dT■

This is Faraday law of electromagnetic induction.

The negative sign signifies Lenz's law. The direction of current (anticlockwise) in the circuit due to the induced emf e is such that the force imposed on the rod (due to the current) opposes the motion of the rod (the motion of the rod is the cause of the current).

It can be seen in the other way also. The direction of current in the circuit is such that the magnetic field produced due to this current is just opposite to the original field B. That is, it opposes the increase in the magnetic flux passing through the circuit (the increase in the magnetic flux is the cause of the generation of current). We may see it from any point of view, the direction of the induced current is always such that it opposes the very cause of its production. This is Lenz's law.

Dimensions of Induced E.M.F.: Numerically, we have
d<b_B ^{e =} ~dT-
, dimensions of e = ₌ ^T^A'*] _{= a} , _A_,
dimensions of t [T]

Organic chemistry articles

Introduction:-
The study of chemistry of carbon compounds is called organic chemistry. According to Lavoisier that all compounds obtained from vegetables and animal sources always contained carbon and hydrogen mainly and nitrogen and phosphorous are also found in some compounds. According to Berzilius organic compounds  are produced from plant and animals only due to presence of some vital force in them.It is called  “Vital force theory”.It is disproved by wholer by producing urea(NH₄ CONH₂) from ammonium cyanate (NH₄CNO)
                                                                 NH₄CNO→ NH₄ CONH₂  
                                   Kolbe synthesized acetic acid (CH₃COOH) from its elements.

Compounds:-

Carbon form millions of compounds due to the following reasons.
1.    High catenation
2.    Tetravalency
3.    Ability to form multiple bonds
4.    Ability to exhibit isomerism

Classification of organic compounds based on carbon skeletion
                     Carbon compounds
Open chain(acyclic)                 (cyclic) closed chain
Aliphatic
Saturated    Unsaturated

Alkanes        Alkenes    Alkynes
Alkanes: Open chain compounds with single bonds between carbon atoms
Ex:  methane and ethane
Alkenes: open chain compounds with atleast one double bond in the carbon chain
Ex: ethylene,propylene
Alkynes: open chain compounds with atleast one triple bond in the carbon chain
Ex:  acetylene,propylene
Alicyclic: Carbon ring with single bond between carbon atoms
Ex: Cyclohexane C₆H₆
Aromatic: planar ring structures with (4n+2)∏ electrons  are called aromatic  according to Huckel rule.Where n is 0,1,2,….
    Ex: pyridine,Furan.

Classification of Carbon compounds on the basis of functional groups:-

Atom or bond or group of atoms in a molecule which is responsible for the characteristic properties of the compound is called functional group

Name	General Formula	Name	Structural Formula
Alkanes	CnH2n+2	Ethane
Alkenes	CnH2n	Ethene
Alkynes	CnH2n-2	Ethyne

Natural Organic Soap

Introduction :
Soap is made by heating animal or vegetable oils with sodium hydroxide. Esters present in fats are broken down to glycerol and sodium salt of fatty acid.

Fat + Sodium hydroxide ------------> Soap + Glycerol

This reaction is called saponification.
Let us discuss the cleaning action of natural organic soap in detail:

Cleaning Action of Natural Organic Soap

The cleaning action of natural organic soap depends on its structure.
E.g. Sodium stearate consists of a long hydrocarbon chain which is hydrophobic (water-hating), attached to an ionic head, which is hydrophilic (water - loving). These molecules dissolve in water because of ionic end to the molecule.

When dissolved in water, the soap molecules lower the surface tension of the water, makiang it wet objects more easily. The molecules also interact with grease and dirt present in the cloth. The hydrophobic hydrocarbon chain is attracted to the grease and become embedded in it. The hydrophilic head of molecule points away from dirt and is attached to water molecule. When water is agitated, the grease is released from the cloth fibre or dish and is completely surrounded by soap molecules. Rinsing with fresh water removes this grease. The use of soap in hard water creates lots of problems because it forms scumbs with hard water. But nowadays synthetic detergents are available which do not scumb witrh hard water. Sodium alkylbenzene - sulphonates were developed in 1970s.

They have a similar long hydrocarbon chain to soap molecules, but the ionic group at hydriphilic head has been changed. The early synthetic detergent molecules were not biodegradable and cause pollution problems in rivers and streams.

Uses of Natural Organic Soap:

• Natural organic soap can be used to avoid or reduce many skin problems.
• Its ingredients have been produced without using fertilizers or pesticides, so it is not harmful to the skin.
• It leaves our our skin feeling clean and moisturised.
• Glycerine, which is a great moisturizer is retained by the natural organic soaps.
• Reduction in the use of toxins helps to create better living environment.
• Most of them are also free from animal fats, which prevents the killing of animals.

Organic chemistry spectroscopy

Introduction 
The study of the interaction between radiation and the matter is called spectroscopy. Molecules in an organic compound have the tendency to absorb specific frequencies according to their structural characteristics. These frequencies can be in the range of visible light, infrared or ultraviolet radiations.

Description of organic chemistry spectroscopy

The electrons in the molecules of an organic compound undergo transition when they absorb or emit light. This is the reason that the color perceived by the organic compounds depends on the absorption of light radiations in the visible range.

Infrared spectroscopy is very successful in organic chemistry.  The types of bonds present in a compound as well as their lattice arrangements can be found by the absorption of IR radiations when they emit thermal radiations. The frequency at which the absorption of the radiation takes place matches the frequency of the vibrating bond.

Nuclear magnetic resonance spectroscopy analyzes the magnetic properties of certain atomic nuclei like hydrogen and carbon which determines their local environments in an organic compound through which the structure of the compound can be determined.

UV spectroscopy is used in highly conjugated organic compounds which absorb UV light or light in the visible regions. When electrons within the atoms are excited from one electronic state to another, their solutions show change in color based on changes in the wavelength due to absorption of visible light by the d electrons. Organic compounds with solvents may either have significant or weak UV absorptions because the pH value and polarity of the solvent do affect the absorption capability of the organic compound.

By passing a beam of IR light through a sample of organic compound the infrared spectrum of the sample can be recorded. On examining the light rays that are transmitted, we get to measure the quantity of energy absorbed at each wavelength. Absorption takes place when the IR frequency is equal to the frequency of the bond. Analysis of these absorption characteristics reveals details about the molecular structure of the sample.

Conclusion for organic chemistry spectroscopy

As complex molecular structures lead to more absorption bands which in turn develops more complex spectra, various types of spectroscopy techniques help in characterization of complex mixtures.

Electricity wind

Introduction

Electric power:- As we know Electric power or elctric current both are same, you have learnt that uncharged boby can be charged by connecting body with a metal wire. In the process of tranfer, charge flows through the wire in a fraction of a second. The flow of electric change constitues an electric currect. With electric power we can run anything like fans, ac , refrigerators, machines, computer almost all the mechanical things you can run by electric power. So electric power is very much important in our daily life.

We are using eletric power almost every second of our daily life and we cannot live without electric power. As we know electric power is not a renewable source of energy we need to produce it own your own. So we have wind energy which is renewable source of energy with the help of wind energy we can produce electric power. This picture show about electric power.

Electricity wind

Wind power :- With the help of wind power we can produce electric power as we know wind blows with the natural phenomenon and we need to source to blow fast wind. Because of different temperature on earht surface wind blows from one direction to another direction and we can utilize this wind energy in different purposes as we can set up a wind turbine and with wind power these turbines will rotate and it will produces mechanical energy and we can use this mechanical energy in any form we can use it by grinding grains , pumping water and most important we can produce electric power by wind energy, just by connecting wind trubines to electric generator we can convert mechanical energy to electrical power. Following figure shows you the image of wind turbine.

Advantages of electric wind power

    As is it renewable source of energy we can produces as much as electric power with the help of wind power just we need to fix wind turbine.
    This is very cheap source of energy and we can produce large amount of electric energy with the help of wind power.
    We can use electric energy produce by wind power in any form.

Static and Current Electricity

Introduction :

The two basic kind of electricity that exist in nature are:  the static electricity and the current electricity.Static electricity is nothing but the collection of uncontrolled electrons which are passing from one body to another body in a movement which is sudden or momentary. Whenever the motion of the electron along a path is a controlled motion then the electricity so produced in the system or circuit is the current electricity.

Examples of static and current electricity

The examples of static electricity:

    The clothes taken out from the dryer and they are stick together

    One can get a shock after walking on the carpet and then suddenly touching something.

The static electricity is generally a nuisance and the hazards of static electricity include the cause of fire. The example of static electricity in which it is produced by rubbing the balloon with the hairs.

Static electricity

Example of current electricity:

The path used in the case of the current electricity is generally a conductor of electricity like a copper wire which can move the electricity from the power plant to the households

Current electricity

Application of Static and Current Electricity

The current electricity is obtained in case when a plug is inserted in a socket, which is generally seen in our homes and this electricity is used to power up the systems like the stereo and the lights. The current electricity is the flow of billions of electrons through the circuit and this flow of electron make a wave of electron which has a voltage of about 120 V. The flow of the current electricity in a system can be taken as the pushing of the electrons through the system through a wire and on the wall on which the socket of electricity is located.

On the other hand, the static electricity occurs only when some of the electrons of a neutral material are moved from their present location to some other location and hence give rise to the electricity and the motion of electron is due to some unknown causes and this electricity is not generally observed. In case of the static electricity no new electron is involved to produce electricity only those electrons which are already there are undergoes some changes hence produces electricity.

A day without electricity

Introduction

A day without electricity is very difficult. Imagining a day without electricity thinking it will be very difficult

Imagine a day without electricity, not just a brief power outage. We all know how inconvenient that day becomes when our electricity is out for only a few hours. How hard it is to remember for that short period of time that the light switch will not produce instant light, the hair dryer will not immediately blow dry our hair, or that we can't even run water into our homes. Our homes and lives have become so dependent on electricity it is really hard to imagine everything that would change without it.

In details

Lifestyles in our own Ozark Mountain region have changed dramatically with the invention of electricity and its establishment into our everyday lives. Have you ever noticed a log cabin built at the very top of a high mountain where it would have a beautiful view? Probably not. Locations were chosen for homes because of accessibility to water, preferably a big spring. Having your home close to a spring meant having cold milk, a cool watermelon in the summer, and plenty of drinking water. Before electricity, a "spring box" would be constructed where the cool spring water would run into it and be deep enough to cover containers of milk, butter, etc. I'm convinced that a spring located close to your home was just about one of the biggest luxuries in those days. Remember, without electricity there were no electric cattle waterers. Drawing water from the well by hand to water a herd of cattle and horses would now seem an impossible task.

A day without electricity
Can we really imagine doing laundry without electricity? Carrying water from the spring, or drawing enough water from the hand-dug water well could prove to quite a day's chore. We really can't imagine the time and effort put into doing a mere "load of laundry" before our electric washers and dryers.