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How to dunk a biscuit without it breaking
Description
Physicist Dr. Len Fisher investigated the mechanics of biscuit dunking and discovered that the best way to prevent them from falling apart is a horizontal dunk, with the coated side facing upward. His research demonstrates how capillary forces draw the liquid into the cookie's pores, and how adjusting the angle can double the time it takes for the biscuit to collapse into the cup.
Original title
איך לטבול ביסקוויט בתה בלי שייפול?
הפיזיקאי ד"ר לנ פישר חקר את המכניקה של טבילת ביסקוויטים ומצא כי הדרך הטובה ביותר למנוע מהם להתפרק היא טבילה אופקית, כשהצד עם הציפוי פונה כלפי מעלה. מחקרו מדגים כיצד כוחות נימיים גורמים למשקה לחדור לנקבוביות העוגייה, ואיך שינוי הזווית יכול להכפיל את הזמן שעובר עד שהביסקוויט קורס אל תוך הכוס.
Video transcript
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