UPSC CAPF (AC) 2025 Paper I · Question 108

Question 108 of the UPSC CAPF (AC) 2025 Paper I (3 August 2025). Try it first, then open the answer and explanation.

1. CAPF 2025 · P-I · Q108 · General Science · Physics

   The larger area under the hysteresis curve (B-H) of a ferromagnetic material depicts

   1. maximum magnetization
   2. extent of demagnetization
   3. extent of lagging
   4. minimum energy

   किसी लोहचुंबकीय सामग्री के शैथिल्य वक्र (B-H) के अधीन बृहत् क्षेत्र क्या दर्शाता है?

   1. अधिकतम चुम्बकन
   2. विचुम्बकन की सीमा
   3. पश्चगमन (lagging) की सीमा
   4. न्यूनतम ऊर्जा
   Show answer

   Answer: (3) extent of lagging

   उत्तर: (3) पश्चगमन (lagging) की सीमा

   Hysteresis means the lagging of the magnetic induction B behind the magnetising field H, and the area enclosed by the B-H loop equals the energy lost as heat per unit volume in each cycle; so a larger loop area shows a greater extent of lagging and greater hysteresis loss (as in hard steel, unlike soft iron with its narrow loop). Maximum magnetization is read from the saturation point of the loop, not from its area. One source reports UPSC's final key as (a).

Answer it in the practice appMake a topic-wise quiz