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चार महीने का बच्चा कैसे बना अरब़पति

चार महीने का बच्चा कैसे बना अरब़पति? जन्म के सिर्फ चार माह बाद यदि कोई बच्चा अरबपति बन जाए तो इसे उसकी किस्मत ही कहेंगे। भारत के एकाग्रह रोहन मूर्ति नाम के बच्चे की किस्मत कुछ इसी प्रकार चमकी है। देश की दूसरी सबसे बड़ी आइटी कम्पनी इंफोसिस के फाउंडर नारायण मूर्ति ने सोमवार अपने चार महीने के पोते एकाग्रह मूर्ति को 240 करोड़ रूपए के शेयरों की हिस्सेदारी का तोहफा देकर उसे शायद देश का सबसे कम उम्र का अरबपति बना दिया है। BSE की फाइलिंग के अनुसार इंफोसिस में अब एकाग्रह रोहन की 15 लाख शेयरों की हिस्सेदारी हो गई है। इसका मतलब अब एकाग्रह रोहन इंफोसिस का 0.04% का हिस्सेदार है। शेयरों के स्थानान्तरण के बाद नारायण मूर्ति के पास कम्पनी के कुल शेयरों का 0.36% हिस्सा बचा है। जिस समय नारायण मूर्ति द्वारा अपने पोते को शेयर देने की खबर बाई उस समय इंफोसिस के शेयरों में गिरावट देखने को मिल रही थी। एकाग्रह रोहन, नारायण मूर्ति तथा सुधा मूर्ति के बेट रोहन मूर्ति और उनकी पत्नि अर्पणा कृष्णन का बेटा है। आपको यह पता होगा कि नोरायण मूर्ति ने अपनी पत्नि सुधा मूर्ति से 10 हजार रूपए उधार लेकर 1981 में इंफोसिस क

Power devices | Power electronics

Power Devices Introduction of power device Power semiconductor diodes are similar to low power pn-junction diodes. Power transistors are identical with npn or pnp signal transistors. Power diodes are constructed with n - layer, this n - layer is called drift region , which exists between p + layer and n + layer. The p + and the n + layers are known as anode, and cathode (substrate) respectively. The n - layer is used to support a large blocking voltage. This n - layer is not present in low power diodes or signal diodes. Note:   The low power diodes and transistors are also known as signal diodes and signal transistors respectively. Difference between Power semiconductor and Signal semiconductor Power semiconductor diode and transistor Signal semiconductor diode and transistor The voltage, current and power ratings of these devices are high. The voltage, current and power ratings are these devices are low.

Types of power diodes | Power electronics

Types of Power Diodes The power diodes are mainly classified into following three categories: General purpose diode The value of t rr for these diodes are vey high, and it is about 25µs. The current rating for general purpose diode is from 1A to several thousand amperes. The voltage rating of general purpose diodes are from 50V to 5kV. Uses The general purpose diodes are used in battery charger. These diodes are also used in electric traction. The general purpose diodes are also used in electroplating. In welding works, the general purpose diodes are very useful. These diodes are used in uninterruptible power supply (UPS) too. Fast recovery diode The value of t rr  of fast recovery diode is low and it about 5µs or less. Its current rating is from 1A to several thousand amperes. The voltage rating of fast recovery diodes are from 50V to 3kV. If we require the voltage rating of fast recovery diode below 400V,

Power diodes | Power electronics

Power diodes Introduction of power diode Power diode is a two layer, two terminal, p-n semiconductor diode. The two terminal of diode are called anode and cathode . Characteristic of power diodes Circuit diagram for characteristic curve of power diode When diode is positive with respect to cathode, diode is said to be forward biased. With increase of V s from zero value, initially diode current I is zero. From V s = 0 to cut-in voltage (threshold voltage or truth-on voltage), the forward diode current is very small. After cut in voltage, the forward diode current increases rapidly and the diode is said to conduct. For Si diode, the value of cut-in voltage is 0.7V When diode conduct, there is a forward voltage drop of the order of 0.8 to 1V. Characteristic curve of power diode When cathode is positive with respect to anode, the diode is said to be reverse biased . In reverse bias condition, a small reverse curre

Introduction of power electronics

Introduction of power electronics Power electronics belongs partly to power engineers and partly to electronics engineers. It means it is the combination of power engineering and electronics engineering. Power engineering is mainly concerned with generation, transmission, distribution and utilization of electric energy at high efficiency. The simple engineering is guided by distortion-less production, transmission and reception of data and signals of very low power level of the order of a few watts, or milliwatts without much consideration of the efficiency. Power electronics is also known as industrial electronics. The apparatus associated with power engineering is based mainly on electromagnetic principles, whereas in electronics engineering they are based on physical phenomenon in vacuum, gases/vapours and semiconductors. This subject concerns the application of electronic-principles into situations that are rated at power levels rather than signal levels. It may a

Applications to atmospheric physics

Kinetic theory plays a major role in atmospheric physics. With the help of kinetic theory we can explain many problems, so here in the lecture Applications to atmospheric physics, we tried to explain about barometric equation, barometric formula, and also estimation of Avogadro’s number. Since the lecture applications to atmospheric physics is explained here in both Hindi and English language, so it is better to understand the student of Hindi and English mediums. This is bilingual lecture and is related to Thermodynamics or thermal physics.

Dulong and Petit's law

Dulong and Petit's law According to Dulong and Petit's law the product of atomic weight and specific heat for all the elements in its solid state is always constant and its value is approximately 6.4.  This law is used to determine the atomic weight of substance.      Dulong and Petit’s law from Kinetic theory According to the law of equi-partition of energy, the average kinetic energy of translation associated with each degree of freedom is 1/2kT. If the oscillatory motion of atom is simple harmonic then in each oscillation the average kinetic energy = Average potential energy.           Total energy associated with each degree of freedom of atom                                               = 1/2 kT + 1/2 kT = kT           Since there are three degrees of freedom for oscillatory motion of each atom           So the total energy of each atom = 3kT           If we consider the 1 gm-atom of any solid at absolute temperature T           So the number of atoms in 1 gm-

Mean kinetic energy of translation

According to kinetic interpretation of temperature the average kinetic energy of translation of molecule of any gas is directly proportional to the temperature and its value for perfect gas is 3/2 kT. In this lecture we have explained about the Mean KE of translation of a gas molecule, Brownian motion, relation between gamma and constitution of gas molecule, degree of freedom, and the law of equipartition of energy in detail. Since the lecture Mean KE of translation of a gas molecule is explained here in both Hindi and English language, so it is better to understand the student of Hindi and English mediums. This is bilingual lecture. This topic is related to Thermodynamics or thermal physics.

Gas laws on the basis of kinetic theory

It is found that the gas laws like Boyle’s law, Charles’ law, Gay Lussac’s law, Avogadro’s law, Dalton’s law of partial pressure, Graham’s law of diffusion can be derived on the basis of kinetic theory. So here in Gas laws on the basis of kinetic theory, we derived and explain all these laws. Since in the lecture Gas laws on the basis of kinetic theory we explain and derive all the above laws on the basis of kinetic theory, it means kinetic theory plays a major role in thermodynamics or thermal physics. All the laws here are explained both in Hindi and English language, so it is better to understand the student of Hindi and English mediums. This is a bilingual lecture. This topic is related to Thermodynamics or thermal physics.

गतिक प्रतिरूप से ताप की व्याख्या | Kinetic interpretation of temperature in Hindi | Thermodynamics | Kinetic theory

गतिक प्रतिरूप से ताप की व्याख्या एक आदर्श गैस का दाब  M= mN m = एक अणु का द्रव्यमान N = 1 ग्राम अणु में अणुओं की संख्या (आवागाद्रो संख्या) निष्कर्ष गैस के अणु की माध्य गतिज ऊर्जा, गैस के परम ताप के समानुपाती होती है। गैस के अणु का वर्ग माध्य वेग, गैस के परम ताप के समानुपाती होता है। किसी वस्तु द्वारा उत्पन्न ऊष्मा की मात्रा इसके अणुओं की कुल गतिज ऊर्जा के बराबर होती है तथा इसका ताप, इसके अणुओं की माध्य गतिज ऊर्जा के समानुपाती होता है। यही ताप की गतिक व्याख्या है। आदर्श गैस समीकरण गतिक प्रतिरूप से ताप की व्याख्या की अधिक जानकारी के लिए https://youtu.be/9X-JyxPvGc8  पर क्लिक करें।

Kinetic theory of gas and Pressure of an ideal gas | L-1 | Thermodynamics

Kinetic theory of gas and Pressure of an ideal gas Postulates of kinetic theory of gases A gas is made of tiny invisible, perfectly elastic particles. These particles are known as molecules . All the molecules of a pure gas are identical and they move continuously in all possible directions with all possible velocities. The gas exerts a pressure on the walls of chamber in which it is filled. The gaseous molecules collide with each other continuously and they traverse a straight line path between any two successive collisions. The size of the molecules is infinitely small as compared to the distance traversed by the molecules in between any two successive collisions. The collisions are instantaneous and there is no loss of kinetic energy in the collisions. The molecules exert no force on each other, except when they collide, and the whole molecular energy is kinetic. The volume of the gaseous molecules is negligible in comparison to the volume of the vesse

Bridge Rectifier

A device which is used to convert alternating current (or voltage) into direct current (or voltage) is known as rectifier, and the process of converting a.c. into d.c. is known as rectification. There are two type of rectifier half wave rectifier and full wave rectifier. A rectifier which converts only half cycle of input a.c. into d.c. is known as half wave rectifier and a rectifier which converts complete cycle of input a.c. into d.c. is known as full wave rectifier. In normal full wave rectifier we use a center taped transformer, which is bulky and costly, so we use a new type of full wave rectifier, known as bridge rectifier. Here in this session we have discussed about the basic of rectifier, definition of half and full wave rectifier, the drawbacks of full wave rectifier. Since our main focus is here on the Bridge Rectifier, so here we also discussed about the construction and working of bridge rectifier, the average value of current, rms value of current, efficiency of bridge

Full wave rectifier

A device which is used to convert alternating current (or voltage) into direct current (or voltage) is known as rectifier, and the process of converting a.c. into d.c. is known as rectification. There are two type of rectifier half wave rectifier and full wave rectifier. A rectifier which converts only half cycle of input a.c. into d.c. is known as half wave rectifier and a rectifier which converts complete cycle of input a.c. into d.c. is known as full wave rectifier. Here in this session we have discussed only about full wave rectifier, and a brief idea of half wave rectifier is also given here. In this lecture we have determined the average value of current, rms value of current, efficiency of full wave rectifier, ripple factor and also about the frequency component. Here we have explained everything in Hindi and in English language, so it is bilingual lecture. This topic is related to electronics and solid state physics.

Half wave rectifier | Electronics | Power supply

Half wave rectifier Rectifier A device which is used to convert alternating current (or voltage) into direct current (or voltage) is known as rectifier The process of converting ac into dc is known as rectification. Principle of rectifier A diode offers a low resistance in forward bias and a high resistance in reverse bias. It means a very small or practically a zero current flows through the circuit, when diode is reverse biased. This principle is used in the working of rectifier. Half wave rectifier (HWR) A rectifier which converts only half cycle of input ac into dc is known as half wave rectifier. In this rectifier an alternating voltage E = E 0  sin ωt is applied at the primary coil of transformer. The output voltage is always positive, but it does not remain constant with respect to time. The output voltage obtained will be pulsating dc voltage. If R f = forward dynamic resistance of diode, R s = resista

Light emitting diode | Electronics | Semiconductor diode

Optoelectronic diode An optoelectronic diode is a diode which includes optics along with electronics. It means optoelectronic diode either emit light or they work when light falls on them. Here we will discuss about light emitting diode as an optoelectronic diode. Light emitting diode (LED) Principle of LED In simple p-n junction diodes (Ge, Si), the energy bands are indirect. When these diodes are forward biased, then the recombination of electron-holes across the junctions starts. When electron jumps from higher energy level to lower energy levels then the energy emitted by electrons in these diode will be in the form of heat and hence we can not see it. In some semiconductor (GaAs), the energy bands are direct. When these semiconductor diodes are forward biased then in the process of recombination of electron-hole pairs, the electron jumps from higher energy level to lower energy levels. The energy emitted during this process lie i

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