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Showing posts from August, 2020

ELECTRICAL SHOCK - CAUSE, SYMPTOMS, FIRST-AID, TREATMENT & SAFETY

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ELECTRICAL SHOCK - CAUSE, SYMPTOMS, FIRST-AID, TREATMENT & SAFETY  In this article you learn about electric shock, its symptoms, first aid, electrical safety and its treatment   An electric shock happens when an electric current passes through your body. This can burn both internal and external tissue and cause organ damage. BELOW TWO PICTORIAL SYMBOL TO ALERT AGAINST ELECTRICAL SHOCK RISK Electric shock is due to the flow of current through your body. This is often from hand to hand or from hand to foot. A shock current as low as 15mA a.c or d.c may be fatal.. obviously the size of shock current is related to the applied voltage and your body resistance. Unfortunately, your body resistance goes down as the applied voltage goes up. This means shock current further increased at high voltages. The size of your body resistance also depends on other factors such as your state of health, the degree of contact with live wires and the dampness on your skin.   Do you know what is t

Important Electrical Tools

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  Important Electrical Tools -   Names with pictures and uses In this article we will see electrical tools used by electrician to perform electrical work. Go through the  pictures to recognize electrical tools. you will find name of tool and its uses,  mentioned below each picture. To complete an electrical work we need some collection of basic hand tools , special tools and measuring instruments. By use of electrical tools we can complete our electrical task easily with less effort and time. Wire crimper – Joining 2 pieces of metal or other ductile material ( usually a wire and a metal plate) by deforming one both of them to hold the other. Wire stripper – for removing an insulation from conductor, without losing conductor core. Used to remove insulation of medium sized wires ranging from gauge #10 to gauge #16. Nose pliers – in abnormal condition , we use this tool to cut a wire. Cutting pliers – It is used to cut a wire. Channel Lock Pliers – are a type of slip joint plier. They

ELECTROMAGNETISM, ELECTROMAGNETIC INDUCTION & FARADAY'S LAW

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  Electromagnetism   Magnetic field Magnetic field is a lines of force surrounding a permanent magnet or moving charged particle. What is magnetic flux? It is defined as the total number of magnetic lines of force passing through a specified area in a magnetic field. Unit of magnetic flux is Weber. You are aware that when an electric current flows through a conductor, a magnetic field is setup around the conductor, in the year 1820, Hans Christian Oersted demonstrated that a current carrying conduct is associated with a magnetic field. You also know that current flow is due to the motion of electrons . Here the conductor is static. Electrons are moving and magnetic field is setup around the conductor. This magnetism is called electro magnetism. Electromotive force Electrons are negatively charged and have potential energy. They move freely from a point of high energy level to a point of low energy level. There is driving influence needed to cause the continuous flow of el

AWARENESS AND RECOGNITION OF ELECTRICAL APPLIANCES

  AWARENESS AND RECOGNITION OF ELECTRICAL APPLIANCES Recognise your domestic appliances Safe use of domestic appliances Electrical consumption of electrical appliances Minimize the electric bill Aware about all specification of electric appliances A domestic appliance is a device which assist in household function like cooking , cleaning, food preservation. They varies in size from small to big. Small appliances are very useful and easy to carry. You can carry it from one place to another without any hassle. You can find it mostly in your kitchen. They includes juicer, electric mixer, micro oven, deep fryers, electric kettles, coffee maker etc. Major appliances are big in size and very difficult to carry from one place to another. They are air conditioners, refrigerators, washing machine etc Safe use of domestic appliances Make sure switch is off before plugging the cord of appliance Unplug all electric appliances when they are not in use or if you are going to clean or

POTENTIAL DIFFERENCE, CURRENT, RESISTANCE, RESISTOR AND ITS COLOR CODING

  POTENTIAL DIFFERENCE, CURRENT, RESISTANCE, RESISTOR AND ITS COLOR CODING The energy transferred due to the movement of unit charge between 2 points in a circuit is termed as potential difference. It is observed that potential difference has the same effect as EMF   Take a battery source ,a resistor, a voltmeter and connecting wire. Now to check the open circuit voltage of the battery, connect the battery terminals to voltmeter. It gives EMF of battery. Now, let connect battery and resistor in series connection. The voltage across battery represents the potential difference across the battery. The current leaves the battery source from the positive terminal and enters the resistor( also known as load) at the positive terminal. The direction of current and EMF are same. The voltage across the resistor represents potential difference. So potential difference is defined as The energy transferred due to the movement of unit charge between two points in a circuit   As long as  

CLASS VII- INTRODUCTION TO ALTERNATING CURRENT AND DIRECT CURRENT

  What is AC & DC? Alternating current u   Obtained from power plant, AC generator u   Current reverse its direction. Current is not unidirectional. u   Frequency of AC is 50Hz (in India) or 60Hz depends on country. u   Flow of electron keep switching direction- forward or backward. u   Safe to transfer over longer city distances and can provide more power. Direct current u   Obtained from battery, fuel cell, solar cell. u   Current always flow from positive to negative terminal of battery. u   Frequency of DC is zero. u   Flow of electron steadily in one direction. u   Voltage of DC can not travel very far until it begins to lose energy.     What is the frequency of alternating current in India ? ( 50 Hz)   u   AC can even be changed to DC by an adapter that you might use to power the battery on your laptop. u   Rectifier is used to convert AC into DC. u   Inverter is used to convert DC into AC. u   For example, for your car an inverter wo

CLASS VIII- FUSE-FUNCTION, TYPES AND IMPORTANCE

  TOPIC u   FUSE ? u   TYPE OF FUSE, USE AND THEIR DIAGRAM u   IMPORTANCE OF FUSE u   POSSIBLE ACCIDENT WITHOUT A FUSE   WHAT IS FUSE AND ITS FUNCTION? u   A fuse is an electrical safety device which is designed to melt and separate in the event of excessive current. u   Fuse connected in series with the component(s) to be protected from over current. In case of overcurrent, fuse blows, which make circuit open and therefore no current supply to component(S). u   Thin piece of fuse wire is contained within a safety sheath to minimize hazards of arc blast, if wire burns open with violent force in case of excess overcurrent. u   Residential wiring uses screw-in fuse, sheath is transparent u   Automotive application uses Cartidge type fuse   u   Fuse are held by spring metal clips of fuse holder. Fuse holder to be good insulator u   Overcurrent carries more heat through wire and component(s), which is primarily reacts on fuse wire and melts it down to protect wi