Recent questions in Physics

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 why the resistance of the conductor increases with the rise in temperature.
Answer : Here is a clear explanation of why the resistance of a conductor increases with a rise in temperature, broken down into a simple analogy and the underlying physics. --- ### Simple Analogy: The ... More collisions** mean more opposition to the flow, which is, by definition, **higher resistance**....

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...

Explain with the help of a circuit diagram, how the value of an unknown resistance can be determined using a Wheatstone bridge?
Answer : ![][1] [1]: https://electrical-engineering.app/?qa=blob&qa_blobid=407323477172242274 ### **Introduction** A Wheatstone bridge is an electrical circuit used for the precise measurement of an ... (R₃) at the balance point has been recorded, the unknown resistance Rₓ can be calculated precisely....

What is drift velocity? Derive expression for drift velocity of electrons in a good conductor in terms of relaxation time of electrons?
Answer : --- ### Part 1: What is Drift Velocity? In a metallic conductor (like a copper wire), the outer electrons of the atoms are not bound to individual atoms. They are free to move throughout the entire volume of ... field. * The magnitude of the drift velocity is given by: $v_d = \frac{e\tau}{m}E$....