This section is especially for preparation of competitive examinations based on previous blogs as discussed as under..................................👇
👉 SI Unit means (International System of unit)
👉 Meter (m) is the length equal to 1650763.73 wavelength in vacuum of the raditions corresponding to the transition between the level 2p10 and 5d5 of the krypton-86 atom.👉 Kilogram(kg) - The unit of mass and is equal to the mass of the international prototype of the kilogram.
👉 Second (s) - The duration of 9192631770 periods of the radiation corresponding to the transition between the two hyperfine level of the ground state of caesium-133 atom.
👉 Ampere(A) -The constant current which ,if maintained in two straight parallel conductors of infinite length ,of negligible circular cross sectional ,and place one meter apart in vacuum ,would produce between these conductors a force equal to 2 X 10-7 newton per meter length.
👉 Kelvin (K) -It is the unit of thermodynamic temperature ,is the fraction 1/273.16of the thermodynamic temperature of the triple point of water.
👉 Candela (cd) -It the unit of luminous intensity ,in the perpendicular direction ,of a surface of 1/600000 square meter of black body at the temperature of freezing platinum under a pressure of 101325 newtons per square meter.
👉 Hertz (Hz) -The frequency of periodic phenomenon of which the periodic time is one second.👉 Newton(N)- Is that force which ,when applied to a body having a mass of one kilogram gives it an acceleration of one meter per second squared.
👉 Joule(J)- The work done when the point of application of a force of one newton is displaced through a distance of one meter in the direction of force.
👉 Watt(W)- It is the unit of power is equal to one joule per second.
👉 Coulomb (C)- The quantity of electricity transported in one second by a current of one ampere.👉 Volt (V) - The difference of electric potential between two points of a conducting wire carrying a constant current of one ampere ,when the power dissipated between these points is one watt.
👉 Farad (F)- The capacitance of an electric capacitor between the plates of which there appears a difference of electric potential of one volt when it is charged by a quantity of electricity by one coulomb.
👉 Ohm (Ω)- The electric resistance between the two points of a conductor when a constant potential difference of one volt, applied between these points produces a current of one ampere in this conductor, provided no electromotive force is generated in the conductor.
👉 Weber(Wb)- The magnetic flux which linking a circuit of one turn ,produces in it an electromotive force of one volt as it is reduced to zero at a uniform rate in one second.
👉 Henery(H)- The inductance of closed circuit in which an emf of one volt is produced when the current in the circuit varies uniformly at the rate of one ampere per second.
👉 Lumen(lm)- The flux emitted within unit solid angle of one steradian of a point source having a uniform intensity of one candela.and Lux (lx) is an illumination of one lumen per square meter.👉 The copper have least resistivity (1.59 µohms/cm-cube) and graphite have higher resistivity (3000 µohms/cm-cube).
👉 The mercury have least melting point (-38.86) and graphite have higher melting point (3500) in degree celsius.
👉 Resistivity depends on materials used in wire.
👉 Fuse wire should have high resistivity and low melting point.
👉 Resistivity of mercury at 4K is Zero.
👉 Two different wattage bulb connected in series then lower wattages bulb glows brighter vice versa in case of parller.
👉 The electric field inside a cylindrical conductor is zero when steady current passes through it.
👉 Ohms law is applicable to all conductors of electricity.
👉 Kirchhoff's first law is based on the principle of law of conservation of charge and second law applicable for energy.
👉 EMF of a cell is a function of its resistance.
👉 Metals approach superconductivity near absolute zero temperature such type of metals are mercury and tin.
👉 Voltage dependent resistor usually made from silicon carbide used for suppress surges.
👉 Variable resistor basically called a light dependent resistor.
👉 The value of conductance is high for good conductor of electricity.
👉 If we check open resistance through an ohm meter reads infinite.
👉 Thermistor has negative coefficient of resistance.
👉 Production of heat due to current is related to Joule's law.
👉 The conductivity is measure as mho/meter.
👉 Ohms law is not applicable for insulators and semiconductors.
👉 Lorentz method is used for measurement of absolute resistance.
👉 Heater coil glow but supply wiring does not glow because resistance of heater coil is more than the supply wires.
👉 Filaments of electric bulbs are usually made of tungsten.
👉 The current carrying capacity of the fuse materials mainly depends on cross-sectional area,length and materials used.
👉 Mainly silver,copper and aluminium materials used as a fuse wire always installed in series circuit and rated as ampere.
👉 The individual components that make the circuit are called circuit elements.Two types of elements active and passive in a circuit.
👉 An energy source is an active element e.g. voltage,current sources.
👉 An element which store energy is called passive elements.
👉 Physically separate elements like R,L,C are called lump elements.
👉 A distributed element is inseparable for electrical purpose. In transmission line has R,L and C along its length and is a distributed element.near
👉 The elements which transmitted energy in either direction are called bilateral element while those allowing transfer of energy in one direction are called unilateral elements like diode,rectifier
👉When the output of an element is linearly related to its input,it is linear element otherwise it is a nonlinear element.
👉 Cloth dryer-100 Watt
👉 Electric shaver-10 Watt
👉 Floor polisher-300 Watt
👉 Hair dryer-500 Watt
👉 Heating Pad-60 Watt
👉 Immersion Heater-700 and 1000 Watt
👉 Iron Automatic-1000 Watt
👉 Radio single circuit-30 Watt
👉 Rapid cooker-1200 to 1600 Watt
👉 Refrigerator-100 to 300 Watt
👉 Roaster-1500 Watt
👉 Television Set-100 to 200 Watt
👉 Toaster-500 to 1000 Watt
👉 Vacuum cleaner-150 to 300 Watt
👉 Washing machine without elect. heater-300 Watt
👉 Washing machine with elect. heater-6300 Watt
👉 Water heaters 8 Litres-1200 to 2000 Watt
👉 Water heater 15 Litres-2000 to 4000 Watt
👉 Water heater 60 Litres-4000 to 6000 Watt
👉 Water heater 80 Litres-4000 to 6000 Watt
👉 SI Unit means (International System of unit)
👉 Meter (m) is the length equal to 1650763.73 wavelength in vacuum of the raditions corresponding to the transition between the level 2p10 and 5d5 of the krypton-86 atom.👉 Kilogram(kg) - The unit of mass and is equal to the mass of the international prototype of the kilogram.
👉 Second (s) - The duration of 9192631770 periods of the radiation corresponding to the transition between the two hyperfine level of the ground state of caesium-133 atom.
👉 Ampere(A) -The constant current which ,if maintained in two straight parallel conductors of infinite length ,of negligible circular cross sectional ,and place one meter apart in vacuum ,would produce between these conductors a force equal to 2 X 10-7 newton per meter length.
👉 Kelvin (K) -It is the unit of thermodynamic temperature ,is the fraction 1/273.16of the thermodynamic temperature of the triple point of water.
👉 Candela (cd) -It the unit of luminous intensity ,in the perpendicular direction ,of a surface of 1/600000 square meter of black body at the temperature of freezing platinum under a pressure of 101325 newtons per square meter.
👉 Hertz (Hz) -The frequency of periodic phenomenon of which the periodic time is one second.👉 Newton(N)- Is that force which ,when applied to a body having a mass of one kilogram gives it an acceleration of one meter per second squared.
👉 Joule(J)- The work done when the point of application of a force of one newton is displaced through a distance of one meter in the direction of force.
👉 Watt(W)- It is the unit of power is equal to one joule per second.
👉 Coulomb (C)- The quantity of electricity transported in one second by a current of one ampere.👉 Volt (V) - The difference of electric potential between two points of a conducting wire carrying a constant current of one ampere ,when the power dissipated between these points is one watt.
👉 Farad (F)- The capacitance of an electric capacitor between the plates of which there appears a difference of electric potential of one volt when it is charged by a quantity of electricity by one coulomb.
👉 Ohm (Ω)- The electric resistance between the two points of a conductor when a constant potential difference of one volt, applied between these points produces a current of one ampere in this conductor, provided no electromotive force is generated in the conductor.
👉 Weber(Wb)- The magnetic flux which linking a circuit of one turn ,produces in it an electromotive force of one volt as it is reduced to zero at a uniform rate in one second.
👉 Henery(H)- The inductance of closed circuit in which an emf of one volt is produced when the current in the circuit varies uniformly at the rate of one ampere per second.
👉 Lumen(lm)- The flux emitted within unit solid angle of one steradian of a point source having a uniform intensity of one candela.and Lux (lx) is an illumination of one lumen per square meter.👉 The copper have least resistivity (1.59 µohms/cm-cube) and graphite have higher resistivity (3000 µohms/cm-cube).
👉 The mercury have least melting point (-38.86) and graphite have higher melting point (3500) in degree celsius.
👉 Resistivity depends on materials used in wire.
👉 Fuse wire should have high resistivity and low melting point.
👉 Resistivity of mercury at 4K is Zero.
👉 Two different wattage bulb connected in series then lower wattages bulb glows brighter vice versa in case of parller.
👉 The electric field inside a cylindrical conductor is zero when steady current passes through it.
👉 Ohms law is applicable to all conductors of electricity.
👉 Kirchhoff's first law is based on the principle of law of conservation of charge and second law applicable for energy.
👉 EMF of a cell is a function of its resistance.
👉 Metals approach superconductivity near absolute zero temperature such type of metals are mercury and tin.
👉 Voltage dependent resistor usually made from silicon carbide used for suppress surges.
👉 Variable resistor basically called a light dependent resistor.
👉 The value of conductance is high for good conductor of electricity.
👉 If we check open resistance through an ohm meter reads infinite.
👉 Thermistor has negative coefficient of resistance.
👉 Production of heat due to current is related to Joule's law.
👉 The conductivity is measure as mho/meter.
👉 Ohms law is not applicable for insulators and semiconductors.
👉 Lorentz method is used for measurement of absolute resistance.
👉 Heater coil glow but supply wiring does not glow because resistance of heater coil is more than the supply wires.
👉 Filaments of electric bulbs are usually made of tungsten.
👉 The current carrying capacity of the fuse materials mainly depends on cross-sectional area,length and materials used.
👉 Mainly silver,copper and aluminium materials used as a fuse wire always installed in series circuit and rated as ampere.
👉 The individual components that make the circuit are called circuit elements.Two types of elements active and passive in a circuit.
👉 An energy source is an active element e.g. voltage,current sources.
👉 An element which store energy is called passive elements.
👉 Physically separate elements like R,L,C are called lump elements.
👉 A distributed element is inseparable for electrical purpose. In transmission line has R,L and C along its length and is a distributed element.near
👉 The elements which transmitted energy in either direction are called bilateral element while those allowing transfer of energy in one direction are called unilateral elements like diode,rectifier
👉When the output of an element is linearly related to its input,it is linear element otherwise it is a nonlinear element.
👉 Cloth dryer-100 Watt
👉 Electric shaver-10 Watt
👉 Floor polisher-300 Watt
👉 Hair dryer-500 Watt
👉 Heating Pad-60 Watt
👉 Immersion Heater-700 and 1000 Watt
👉 Iron Automatic-1000 Watt
👉 Radio single circuit-30 Watt
👉 Rapid cooker-1200 to 1600 Watt
👉 Refrigerator-100 to 300 Watt
👉 Roaster-1500 Watt
👉 Television Set-100 to 200 Watt
👉 Toaster-500 to 1000 Watt
👉 Vacuum cleaner-150 to 300 Watt
👉 Washing machine without elect. heater-300 Watt
👉 Washing machine with elect. heater-6300 Watt
👉 Water heaters 8 Litres-1200 to 2000 Watt
👉 Water heater 15 Litres-2000 to 4000 Watt
👉 Water heater 60 Litres-4000 to 6000 Watt
👉 Water heater 80 Litres-4000 to 6000 Watt
