Current Electricity – Hub of related Posts

Ohm’s law is valid for metal conductors provided the temperature and other physical conditions remain constant. The resistance of the material changes with temperature. Hence for changing temperature the V-I ...
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In this post, we will solve a set of Physics Numericals on electric charge and its current, time relationship. Formulas Used Current is a rate of flow of electric charge ...
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In this post, we will solve numerical questions or problems related to the emf of a cell and internal resistance. We will also use the concepts of terminal potential difference, ...
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In this post, we will discuss the Seebeck effect or thermoelectric effect and other related points like thermocouple, thermoelectric emf, thermoelectric series, variation in thermoelectric emf with temperature, Neutral and ...
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In this post, we will discuss some applications of the heating effect of current (applications of Joule heating). Also, read this post on Joule Heating numerical: heating effect of electric ...
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In this post, we will discuss the heating effect of current, and Joule's Law of heating. Class 10 students should find this useful as this post covers Joule's Law of ...
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The temperature dependence of resistance of a conductor can be expressed with the formula R2 = R1 ( 1 + α t), where α is the temperature coefficient of resistance ...
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The variation of resistivity of a metallic conductor, an alloy, a semiconductor, or an insulator with an increase in temperature is not the same in all cases. Temperature dependence of ...
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In this post, we will derive the equation j = sigma e and we will do the derivation using Ohm's law equation (V=IR). Obtaining this equation vec J = σ ...
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Resistance R of the conductor is the ratio of the potential difference to the current. R =V/I. Now, let's find out the dimension of resistance. (Dimensional formula) Dimension of resistance ...
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Resistivity or specific resistance - While deriving Ohm's Law with the help of drift velocity equations, we got the expression or formula of resistance as follows: R = [(mL)/(ne2τA)]. Here, ...
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Derivation of Ohm's Law class 12 - Here, in this post, we will derive Ohm's Law using drift velocity equations following the class 12 syllabus. Know more about the fundamentals ...
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In this post, we will see how the drift velocity of an electron is related to its mobility. The drift velocity of an electron can be expressed as vd = ...
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In this post, we will derive the drift velocity formula and understand the concepts of the drift velocity of an electron. Drift velocity formula derivation | derive drift velocity equation ...
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In this post, we will present the drift velocity formula or equation in terms of different variables like the mobility of an electron, electric current, current density, relaxation time, electric ...
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This post is a compilation of a set questions with answers related to electric current flow and electric shock. What levels of current are dangerous? Approximately 1 mA (0.001 A) ...
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The power formula expresses fundamental relationships among power, current, and voltage. On occasion, you may be asked to calculate any one of the three variables in this equation, given the ...
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Ohm’s Law expresses fundamental relationships among voltage, current, and resistance. On occasion, you may be asked to calculate any one of the three variables in this equation, given the other ...
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When current flows through the material of a circuit, such as the metal of the connecting wires, the material of the circuit gets in the way of the flow of ...
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The image below shows a list of equations and formulae from the chapter "Electricity" of the GCSE Physics syllabus. This is also helpful for all other equivalent boards like CBSE, ...
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In this post, we have compiled a bunch of interesting numerical problems on Resistivity and Conductivity. These are Solved numerical problems (Worked Solutions). Resistivity and Conductivity numerical problems (solved worksheet) ...
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In this post, we will discuss Kirchhoff’s second law, or Kirchhoff's Voltage Law (also known as KVL, Kirchoff's Loop Rule, or Kirchoff's Loop law) with an example or case study ...
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In this post on the Heating effect of electric current class 10 Numericals, we will list down the Heating Effect formulas or Equations of electric power and energy. And, then ...
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In this post, we are going to discuss different ways of measuring the resistance of a component. Resistance is defined as R = V/I. This obviously gives ways of measuring ...
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This post presents a few important numerical problems in physics that you can solve using the concepts of resistivity. If you want a quick revision to memorize the resistivity formula ...
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Alternating Current,(AC) is a current that changes direction cyclically, passing first in one direction, then in the other through a circuit. Such alternating currents are produced by generators and other ...
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In some materials, electrons move easily from atom to atom. In others, the electrons move with difficulty. And in some materials, it is almost impossible to get them to move ...
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In this post, we will have some pointers on the Conservation of Charge & Energy in electrical Circuits. Charge Doesn’t ‘Leak Away’ Anywhere — it’s Conserved in electrical circuits. Energy ...
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Ammeters measure the current of a circuit, and voltmeters measure the voltage drop across a resistor. Ammeters and voltmeters are cleverly designed because it is important in the design to ...
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Gustav Kirchhoff, an eminent German physicist is the person behind Kirchhoff’s first law dealing with electric current. This law is also known as Kirchhoff’s Current Law or KCL. The KCL ...
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The numerical problems in this post are based on the drift velocity of electrons and electric current. Electric Current is expressed as I = nAve ( see the derivation of ...
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What is the Internal Resistance of cells & how it affects the current flow in a circuit? All electric cells are made of materials that have resistance. The resistance of ...
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Most charge carriers, like electrons, move slowly. Free electrons repeatedly collide with the positive metal ions as they drift through the wire towards the positive terminal. The reason that electric ...
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Here we will derive the equation showing the relationship between current and drift velocity. The drift velocity is the average velocity of the free charges and it is in the ...
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The objective of this post is to present the resistivity of different materials in a table. Let's do that first. The resistivity of different materials showed in a table at ...
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Figure 1 below presents 17 circuit symbols for a variety of circuit components like cell, battery, switch open, switch closed, ammeter, voltmeter, motor, resistor, thermistor, fuse, diode, LED (Light Emitting ...
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Voltages in series circuits and parallel circuits - Let's see how total voltage in series circuits and parallel circuits are calculated. Voltages in series circuits A series circuit has no ...
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Here we will see how current flows through series and parallel circuits. Currents in series circuits In a series circuit, devices are connected so there is only one closed path ...
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In this post, we will cover How to find the Relation between resistance and resistivity through a simple experiment. It's basically deriving the resistivity formula with our understanding of electrical ...
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I-V graph of a Thermistor and I-V graph of a filament bulb are not identical. Now the question is: How to identify the I-V graph of a Thermistor and the ...
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In this post, we will study a simple parallel circuit. Then we will derive the equivalent resistance formula in a parallel circuit. Using this formula, we will solve numerical problems ...
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In this post, we will study simple series circuits with the help of a series circuit diagram. We will also go through related topics like resistance in series or resistors ...
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The direction of the current: We will discuss this to find out answers to two related questions here. These questions are (1) What is the direction of conventional current? (2) ...
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If two charged bodies are connected by a metallic wire, electrons start flowing from the body having more electrons (negatively charged body), to the body with less electrons (positively charged ...
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Ohm's Law Problems in physics: The numerical problems from Ohm's law topic are apt for class 9 physics and class 10 physics courses offered by boards like CBSE, ICSE. Here ...
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figure 1: I-V characteristic of a metallic conductor (Ohmic) Ohm’s Law states: The potential drop across a resistor is proportional to the current passing through the resistor: V ∝ I ...
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