Hot questions

A silver wire has a resistance of 2.1 Ohm at 27.5 degree C , and a resistance of 2.7 Ohm at 100 degree C . Determine the temperature coefficient of resistivity of silver.
Answer : ### 1. Understand the Principle The relationship between resistance and temperature for most metals (like silver) over a moderate temperature range is approximately linear and can be described by the formula: $R_2 = ... 00394 °C⁻¹** Alternatively, in scientific notation: **α = 3.94 x 10⁻³ °C⁻¹**...

A battery of emf 10 V and internal resistance 3 Ohm is connected to a resistor. If the current in the circuit is 0.5 A, what is the resistance of the resistor? What is the terminal voltage of the battery when the circuit is closed?
Answer : ### Given Information: * **EMF of the battery (E):** 10 V * **Internal resistance (r):** 3 Ω * **Current in the circuit (I):** 0.5 A --- ### 1. What is the resistance of the ... text{V}$ Both methods give the same result. **Answer:** The terminal voltage of the battery is **8.5 V**....

Six lead-acid type of secondary cells each of emf 2.0 V and internal resistance 0.015 Ohm are joined in series to provide a supply to a resistance of 8.5 Ohm . What is the current drawn from the supply and its terminal voltage?
Answer : ### Given Data: * Number of cells, **n = 6** * EMF of each cell, **E_cell = 2.0 V** * Internal resistance of each cell, **r_cell = 0.015 Ω** * External resistance (load), **R = 8.5 Ω ... The current drawn from the supply is **1.40 A**. * The terminal voltage of the supply is **11.9 V**....

Three resistors 1 Ohm , 2 Ohm and 3 Ohm are combined in series. What is the total resistance of the combination?
Answer : When resistors are combined in series, the total resistance is the sum of the individual resistances. The formula is: R_total = R1 + R2 + R3 Given the values: * R1 = 1 Ω * R2 = 2 Ω * R3 = 3 Ω ... = 1 Ω + 2 Ω + 3 Ω = 6 Ω So, the total resistance of the combination is **6 Ohms**....

Explain the uses of safety rubber hand gloves and rubber mats in electrical engineering.
Answer : In electrical engineering, safety is paramount. Two of the most fundamental and critical pieces of Personal Protective Equipment (PPE) are **safety rubber hand gloves** and **insulating rubber ... environment and preventing a worker's body from becoming the path of least resistance for electricity....

Is ohm’s law universally applicable for all conducting elements? If not, give examples of elements which do not obey Ohm’s law.
Answer : The answer is no, **Ohm's law is not universally applicable for all conducting elements.** Ohm's law is an empirical rule, not a fundamental law of nature. It accurately describes the ... under stable conditions, but it is far from a universal law for all materials that conduct electricity....

Three identical cells, each of emf. 2V and unknown internal resistance are connected in parallel. This combination is connected to a 5 ohm resistor. If the terminal voltage across the cell is 1.5 volt. What is the internal resistance of each cell? Hence define the internal resistance of a cell?
Answer : ### Part 1: Calculating the Internal Resistance Here's how we can find the internal resistance of each cell. **Given Data:** * Electromotive force (EMF) of each cell, E = 2 V * Number of identical cells ... . * **I** is the current flowing from the cell. * **r** is the internal resistance....

Define emf. of a cell? On what factors does it depend?
Answer : ### Definition of EMF (Electromotive Force) The **EMF (Electromotive Force)** of a cell is defined as the maximum potential difference between its two terminals when no current is being drawn ... *, not its EMF. A larger distance increases the path ions must travel, increasing internal resistance....

Explain the reasons for failure of gaseous and solid dielectric materials used in electrical engineering application.
Answer : ### **Introduction to Dielectric Failure** A dielectric material is an electrical insulator that can be polarized by an applied electric field. Its primary function in electrical engineering is to ... Often a slow, aging-related process - Highly sensitive to impurities, voids, and moisture |...

Given n resistors each of resistance R, how will you combine them to get the (i) maximum (ii) minimum effective resistance? What is the ratio of the maximum to minimum resistance?
Answer : The two fundamental ways to combine resistors are in **series** and in **parallel**. These two configurations yield the maximum and minimum possible resistances, respectively. --- ### (i) Maximum Effective Resistance To obtain the * ... {min} = R/n$ | | **Ratio** | $R_{max} / R_{min}$ | $n^2$ |...