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Showing posts from November, 2016

Group-VII-B Services

tamil nadu public service commission invited application through online on post of group vii-b services Applications are invited only through online mode upto 24.12.2016 from applicants professing Hindu Religion only for direct recruitment against the vacancies (2014 – 2015, 2015-2016 and 2016-2017) for the post of Executive Officer, Grade-III included in Group-VII-B Services. Only persons Professing the Hindu Religion as required by Section 10 of the Tamil Nadu Hindu Religious and Charitable Endowments Act- 1959 (Tamil Nadu Act 22 of 1959) are eligible to apply Name of the Post :EXECUTIVE OFFICER, GRADE-III No. of vacancies : 29 Scale of pay :Rs.5200-20200+2800 Grade Pay (PM) (PB1) Date of Notification 25.11.2016 Last date for submission of applications 24.12.2016 Date of Written Examination :29.04.2017 Paper - I====10:00 A.M. to 1:00 P.M. Paper - II =====2:30 P.M. to 5:30 P.M. Minimum Age :25 years Maximum age :         Scheduled Caste / Scheduled Caste (Ar

Tnpsc announced Group-VIII exam

Applications are invited only through online mode upto 24.12.2016 from applicants professing Hindu Religion only for direct recruitment against the vacancies (2014 - 2015, 2015 - 16 and 2016 - 17) for the post of Executive Officer, Grade-IV included in Group-VIII Services :- Only persons professing the Hindu Religion as required by Section 10 of the Tamil Nadu Hindu Religious and Charitable Endowments Act- 1959 (Tamil Nadu Act 22 of 1959) are eligible to apply. Name of the Post and Post Code  :EXECUTIVE OFFICER,GRADE-IV (Post Code: 1655) Name of the Service :Tamil Nadu Hindu Religious and Charitable Endowments Subordinate Service No. of vacancies :49 Scale of pay :Rs.5200 - 20,200 +Rs.2400/- Grade Pay (PM)(PB1) IMPORTANT DATES:-        Date of Notification:                                       25.11.2016        Last date for submission of applications:       24.12.2016        Last date for payment of Fee through Bank:  27.12.2016        Date of Written Examina

What is Heat?

The degree of hotness or coldness of a body or environment. A measure of the warmth or coldness of an object or substance with reference to some standard value. A measure of the average kinetic energy of the particles in a sample of matter, expressed in terms of units or degrees designated on a standard scale. A measure of the ability of a substance, or more generally of any physical system, to transfer heat energy to another physical system. Any of various standardized numerical measures of this ability, such as the Kelvin, Fahrenheit, and Celsius scale As mentioned , the first two bullet points have rather obvious meanings. The third bullet point was the topic of  the previous page in this lesson . The fifth bullet point was the definition that we started with as we discussed temperature and the operation of thermometers; it was the topic of  the second page in this lesson . That leaves us with the fourth bullet point - defining temperature in terms of the ability of a subst

Heat and Temperature

Heat, energy and temperature pervade our lives. Just think about it. We give attention to hot and cold in deciding what we wear during the day, at night and when we go to bed. We think about the topic when deciding how many covers, if any at all, we will wrap in or sleep under at night in order to maintain  the right temperature . Many of us have heating and cooling systems in our homes, schools and work places that control the temperature during the day and night to keep us as comfortable as possible without spending too much money. We install fans or use portable fans in our homes to keep us comfortable. Most of us have cars equipped with heating and air conditioning systems; some may even have meters in their cars that register the indoor and outdoor temperatures. Many of us watch and listen to weather reports, especially the forecasted temperatures, with great interest so that we can make decisions about what to wear and what to do on the following day Our bodies are highly sens

magnetism part 2

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Magnetic Fields  Force On A Current Carrying Wire In A Magnetic Field You will be familiar with the basic notion of a magnetic field , in which magnetic materials experience a magnetic force.  However it is worth revising some of the basic ideas that you will have come across in early secondary school. Revision Magnetic fields can be shown by field lines, which go from North to South. The field lines in a strong magnetic field are more closely packed than in a weak field. Unmagnetised materials are attracted to either pole. Like poles repel; unlike poles attract. In the Earth’s magnetic field, the North pole will align itself to point to the North, if the magnet is allowed to swing freely. The Earth has a magnetic field like a bar magnet.  Notice that the S-pole is under the North geographic pole.  Be careful not to be confused by this.

Magnetism

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In ancient times Greece people found a rock that attracts iron, nickel and cobalt. They call them as “magnet “and magnetism comes from here. These rocks were used later by Chinese people to make compasses. Later scientists found that, magnets have always two poles different from electricity. Magnets have two ends or faces called “poles” where the magnetic effect is highest. In last unit we saw that there is again two polarities in electricity, “-“charges and “+” charges. Electricity can exist as monopole but magnetism exists always in dipoles North Pole (represented by N ) and South Pole (represented by S) . If you break the rock into pieces you get small magnets and each magnet also has two poles N and S. Same poles of the magnet like in the electricity repel each other and opposite poles attract each other. Strengths of these forces depend on the distance between the poles and intensity of the poles. Types of Magnets In nature Fe 3 O 4 is used as magnet. However, th

DC vs. AC

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In the Current Electricity section, you learned about electric charge, current, voltage and other related topics. But, just because you have a voltage does not mean electric current will flow. Electrons also need a complete loop of conductive material to flow, called a closed circuit . Let's look at a light switch. When you turn the switch "on", the switch creates a path that conducts electricity and electrons start to move—meaning electric current flows—and the light turns on. As soon as you turn the switch "off", the path is broken and electrons can no longer flow. The switch is like a drawbridge; switching it on is letting down the bridge so the electrons can cross (just like cars crossing a bridge) and provide energy to the light bulb. Illustration of how electric current can move through a closed loop of conductive material (left figure) but stops flowing whenever the loop is broken (right figure). This figure shows how a light bulb l

Electricity part 2

Making Charges Flow We now have all the tools to make charges flow. Electrons in atoms can act as our charge carrier , because every electron carries a negative charge. If we can free an electron from an atom and force it to move, we can create electricity. Consider the atomic model of a copper atom, one of the preferred elemental sources for charge flow. In its balanced state, copper has 29 protons in its nucleus and an equal number of electrons orbiting around it. Electrons orbit at varying distances from the nucleus of the atom. Electrons closer to the nucleus feel a much stronger attraction to the center than those in distant orbits. The outermost electrons of an atom are called the valence electrons , these require the least amount of force to be freed from an atom. Using enough electrostatic force on the valence electron–either pushing it with another negative charge or attracting it with a positive charge–we can eject the electron from orbit around the atom

Electricity part 1

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Electricity is all around us–powering technology like our cell phones, computers, lights, soldering irons, and air conditioners. It’s tough to escape it in our modern world. Even when you try to escape electricity, it’s still at work throughout nature, from the lightning in a thunderstorm to the synapses inside our body. But what exactly is electricity? This is a very complicated question, and as you dig deeper and ask more questions, there really is not a definitive answer, only abstract representations of how electricity interacts with our surroundings. Electricity is a natural phenomenon that occurs throughout nature and takes many different forms. In this tutorial we’ll focus on current electricity: the stuff that powers our electronic gadgets. Our goal is to understand how electricity flows from a power source through wires, lighting up LEDs, spinning motors, and powering our communication devices. Electricity is briefly defined as the flow of electric charge, b

Force, Motion, and Energy

Work: the force used to move something There are 2 basic types of energy:          A. Kinetic: the energy gotten from a moving object. A car going down a hill has kinetic energy.           B. Potential: energy waiting to be used (stored energy). A ball waiting to be dropped. The heavier an object is or the higher it is gives it more potential energy       Force: any push or pull that causes an object to move, stop, or change speed or direction Friction: a resistance to motion because objects are rubbing against each other.     Friction causes heat. Bike or car brakes use friction to slow them down. Inertia: when your body is riding in a car and the brakes are slammed on your body keeps moving forward that is inertia. Another example is when you are sitting on a sled and your dad jerks on the rope and you fall back (stay at rest) because of inertia. gravity: an unseen force that pulls two objects toward each other Heat Energy- moving molecules where the heat finds cold

Physical quantities, standards and units

PHYSICAL QUANTITIES AND THEIR SI BASE UNITS Following is the list of Physical Quantities and their SI Base Units and Symbols. Physical Quantity Unit Symbol length meter m mass kilogram kg time second s electric current ampere A thermodynamic temperature kelvin K amount of substance mole mol luminous intensity candela cd SOME SI DERIVED UNITS Physical Quantity Unit Symbol area square meter m 2 volume cubic meter m 3 frequency hertz Hz mass density (density) kilogram per cubic meter kg/m 3 speed, velocity meter per second m/s angular velocity radian per second rad/s acceleration meter per second squared m/s 2 angular acceleration radian per second squared rad/s 2 force newton N pressure pascal Pa work, energy, quantity of heat joule J power watt W quantity of electricity coulomb C potential difference, electromotive force volt V electric field volt per meter V/m electric resistance ohm capacitance farad F magnetic flux weber Wb inductance h

Scalars and Vectors

Scalars: A scalar quantity requires only size (magnitude) to completely describe it. Vectors: A vector quantity requires size (magnitude) and a direction to completely describe it. Here are some vector and scalar quantities:                          Scalar                               Vector                           time                                   force                           temperature                      weight                           volume                          acceleration                           distance                          displacement                           speed                                velocity                           energy                                momentum                           mass                                  impulse                           frequency                          power ** Familiarise yourself with these scalar and vector quantities ** The knowledge and understanding content for this unit

National Laboratories and Research Institutes of India

Here is a concise and broad  list of major Research Institutes and Laboratories of India. Name                                                                                                     Place Ahmedabad Textile Industry’s Research Association(ATIRA) Ahmedabad, Gujarat All India Institute of Hygiene and Public Health                         Kolkata, West Bengal All India Institute of Hygiene and Public Health (AIIHPH)    Kolkata, West Bengal All India Institute of Medical Sciences (AIIMS)                         New Delhi, Delhi All India Institute of Speech & Hearing(AIISH)                         Mysore, Karnataka Automotive Research Association of India (ARAI)                 pune, Maharashtra  Bhabha Atomic Research Center (BARC)                                 Mumbai, Maharashtra Birbal Sahni Institute of Paleobotany (BSIP)                         Lucknow, Uttar Pradesh Birla Industrial & Technological Museum (BITM)                 Ko