Showing posts with label NEET Solved Papers. Show all posts
Showing posts with label NEET Solved Papers. Show all posts

NEET 2025 physics semiconductor devices full wave rectifier question

 This tutorial provides a detailed walkthrough of a NEET 2025 physics problem from the Semiconductor Devices chapter, focusing specifically on the operation of a Full-Wave Rectifier circuit.

Core Concepts Covered:

The video explains the behavior of diodes  in a center-tapped full-wave rectifier system:

  • Circuit Analysis: The problem features an input supply voltage V_{in} = 220 \sin(100 \pi t) and asks to determine the state of the diodes at a specific time, t = 15 ms.

  • Frequency & Time Period: The instructor demonstrates how to calculate the time period (T) of the AC supply from the given angular frequency (omega = 100 \pi).

  • Diode Biasing:

    • During the first half-cycle (0 to 10 ms), one diode is forward-biased while the other is reverse-biased.

    • At t = 15 ms, which falls within the second half-cycle (10 to 20 ms), the polarity of the secondary transformer reverses.

    • Consequently, D_2 becomes forward-biased (conducting), while D_1 becomes reverse-biased (non-conducting) [02:17].

Key Takeaways for Students:

  • Identify the Phase: Learn to determine which part of the AC cycle the circuit is in by comparing the given time (t) to the calculated time period (T).

  • Role of the Center Tap: Understand how the center-tapped transformer provides out-of-phase voltages to the two diodes, allowing for full-wave rectification [03:07].

  • Quick Exam Strategy: The video highlights how to quickly eliminate incorrect options by focusing on the half-cycle logic.



NEET 2025 Finding Diameter using vernier callipers

 Master the essentials of measurement with this simple guide to solving a NEET 2025 physics problem on Vernier Callipers. Whether you're a student or a curious learner, this video breaks down how to find the diameter of an object with precision!

What You Will Learn:

In this tutorial, we solve a real exam question step-by-step, focusing on how to correctly read a Vernier Calliper and account for errors.

  • The Final Reading Formula: Learn the fundamental rule for calculating any measurement: Main Scale Reading (MSR) + (Vernier Coincidence × Least Count) ± Zero Correction.

  • Calculating Least Count: Understand how to find the smallest measurement a device can take by comparing Main Scale Divisions to Vernier Scale Divisions.

  • Handling Zero Errors: Discover why we subtract an "extra" reading of 0.1 cm to ensure the final result is perfectly accurate.

  • Step-by-Step Math: Follow along as we convert millimeters to centimeters and use an organized approach to find the final diameter of 4.98 cm.

Video Highlights:

  • [00:45] - Breakdown of the Final Reading formula.

  • [02:12] - Why and how to apply Zero Correction.

  • [02:46] - The secret to calculating the Least Count.

  • [04:18] - Converting scale divisions into usable measurements.

  • [06:32] - Reaching the final answer of 4.98 cm.