NEET Physics Current Electricity : Multiple Choice Previous Years Questions MCQs 2  Summary and Q&A
TL;DR
Understanding the relationship between potential differences and readings of voltmeters, calculating equivalent resistance, and determining the time needed for electroplating.
Questions & Answers
Q: How can you determine the relationship between the potential differences of voltmeters A, B, and C in the circuit?
The potential differences across voltmeters A, B, and C are the same because B and C are in parallel. Thus, VA = VB = VC.
Q: How can you simplify the circuit and calculate the equivalent resistance?
By replacing voltmeters B and C with a single resistance (R parallel), which is equal to R, the circuit can be simplified, and the equivalent resistance can be calculated.
Q: In question number five, how is the current supplied by the battery calculated?
First, the equivalent resistance of the circuit is calculated by considering the Wheatstone Bridge arrangement. Then, using Ohm's law (I = V/R), the current is determined as 0.6 A.
Q: How is the time needed for electroplating calculated in question number six?
The weight of silver to be deposited is determined as 0.375 g. Using the electrochemical equivalent of silver (11.8 x 10^7 kg/C), the current (0.8 A), and the formula t = m/(ECE * I), the time is calculated as 397 seconds or 6 minutes and 37 seconds.
Summary & Key Takeaways

The video explains the relationship between potential differences and voltmeter readings in a circuit with multiple voltmeters.

The concept of equivalent resistance is introduced, and the process of calculating it is shown.

The video also demonstrates how to calculate the time needed for electroplating a metal plate with a specific weight of silver.