Hot questions

Two electric bulbs A and B are marked 220V , 40W and 220V 60W respectively. Which one has a higher resistance?
Answer : **The 40W bulb (Bulb A) has a higher resistance.** Here's the detailed explanation of why: ### The Relationship The relationship between Power (P), Voltage (V), and Resistance (R) is given by ... to get more water through a pipe; you need a wider pipe (less resistance) to increase the flow rate....

Why do we prefer a potentiometer to measure the emf of a cell rather than a voltmeter?
Answer : The primary reason we prefer a potentiometer to measure the EMF of a cell is that **a potentiometer draws no current from the cell at the point of measurement.** A voltmeter, by its ... method ensures no current is drawn, thereby eliminating any error caused by the source's internal resistance....

State significance of earthing. Draw and explain pipe earthing. State the values of earth resistances for : (i) Substation (ii) Residential wiring (iii) H.T. Line (iv) L.T. Line
Answer : ### 1. Significance of Earthing Earthing (or grounding) is a fundamental safety measure in any electrical installation. Its primary significance is to protect people, equipment, and property from ... to consumers. [1]: https://electrical-engineering.app/?qa=blob&qa_blobid=3390146307772186646...

A set of n-identical resistors, each of resistance R ohm when connected in series have an effective resistance of X ohm and when the resistors are connected in parallel the effective resistance is Y ohm. Find the relation between R , X and Y ?
Answer : Let's break this down step-by-step to find the relationship between R, X, and Y. ### 1. Resistors in Series When resistors are connected in series, their total effective resistance is the sum of ... the **geometric mean** of the total series resistance (X) and the total parallel resistance (Y)....

A battery of emf E and internal resistance r sends a current, I1 , I2 when connected to an external resistance of R1 , R2 respectively. Find the emf. and internal resistance of the battery.
Answer : Let's derive the expressions for the electromotive force (EMF) and the internal resistance of the battery step-by-step. ### Understanding the Setup The core principle we'll use is Ohm's law applied to the entire circuit. For a ... $$ **EMF (E):** $$ E = \frac{I_1 I_2 (R_1 - R_2)}{I_2 - I_1} $$...

State and explain Kirchhoff’s law?
Answer : Kirchhoff's laws are two fundamental principles used to analyze electric circuits. They were formulated by Gustav Kirchhoff in 1845 and are based on the conservation of charge ... =blob&qa_blobid=16131873694589351449 [2]: https://electrical-engineering.app/?qa=blob&qa_blobid=10917265924274549047...

The storage battery of a car has an emf of 12V . If the internal resistance of the battery is 0.4 Ohm , what is the maximum current that can be drawn from the battery?
Answer : The maximum current that can be drawn from the battery is **30 Amperes (A)**. --- ### Detailed Explanation #### 1. Understand the Concepts * **EMF (Electromotive Force, $\mathcal{E ... even explode. This calculation is a theoretical maximum. **Never attempt to short-circuit a car battery.**...

In a potentiometer arrangement, a cell of emf 1.25V gives a balance point at 35.0cm length of the wire. If the cell is replaced by another cell and the balance point shifts to 63.0cm , what is the emf of the second cell?
Answer : ### Principle The working principle of a potentiometer is that the potential drop across any portion of a wire of uniform cross-section is directly proportional to the length of that portion, provided a constant current flows ... 2.25 V** ### Answer The EMF of the second cell is **2.25 V**....

Draw and explain the use of : (i) Combination plier (ii) Tester (iii) Wire Striper (iv) Hammer
Answer : Cutter cum Insulation Remover : ![][1] [1]: https://electrical-engineering.app/?qa=blob&qa_blobid=7558183951160707100...

A Carbon resistor has three strips of red colour and a gold strip. What is the value of the resistor? What is its tolerance?
Answer : The value of a carbon resistor is determined by the standard resistor color code system. For a 4-band resistor: * **Band 1:** First significant digit * **Band 2:** Second significant ... a new resistor with these color bands will have an actual resistance somewhere between 2090 Ω and 2310 Ω....