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Surface energy ratio when a drop splits into or forms from equal droplets

This type of question, asked 12 times: May 2021 S1, 11 May 2023 S1, 16 May 2023 S2, 12 May 2024 S1, 12 May 2024 S2, 14 May 2024 S2, 20 Apr 2025 S1, 20 Apr 2025 S2, 11 Apr 2026 S2, 13 Apr 2026 S1, 13 Apr 2026 S2, 16 Apr 2026 S2. All 14 questions below, oldest first.

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  1. Question 1

    May 2021 S1

    50
    One thousand small water drops of equal radii combine to form a big drop. The ratio of final surface energy to the total initial surface energy is

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  2. Question 2

    11 May 2023 S1

    6
    A big water drop is formed by the combination of 'n' small water droplets of equal radii. The ratio of the surface energy of 'n' droplets to the surface energy of the big drop is

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  3. Question 3

    16 May 2023 S2

    36
    A liquid drop having surface energy EE is spread into 512 droplets of same size. The final surface energy of the droplets is

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  4. Question 4

    12 May 2024 S1

    18
    A spherical drop of liquid splits into 1000 identical spherical drops. If E1E_{1} is the surface energy of the original drop and E2E_{2} is the total surface energy of the resulting drops, then E1E2=x10\frac{E_{1}}{E_{2}}=\frac{x}{10}. Then value of xx is

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  5. Question 5

    12 May 2024 S2

    41
    Eight small drops of mercury each of radius 'rr' coalesce to form a large single drop. The ratio of total surface energy before and after the change is

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  6. Question 6

    14 May 2024 S2

    2
    1000 small water drops of equal size combine to form a big drop. The ratio final surface energy to the total initial surface energy is

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  7. Question 7

    20 Apr 2025 S1

    26
    The surface energy of a liquid drop is ' VV '. It is sprayed into 1000 equal droplets. The surface energy of all the droplets is

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  8. Question 8

    20 Apr 2025 S1

    32
    A liquid drop having surface energy E is spread into 729 droplets of same size. The final surface energy of the droplets is

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  9. Question 9

    20 Apr 2025 S2

    46
    A liquid drop having surface energy EE is sprayed into 512 droplets of same size. The final surface energy is

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  10. Question 10

    11 Apr 2026 S2

    109
    A liquid drop having surface energy E is sprayed into 512512 droplets of the same size. Then the final surface energy is

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  11. Question 11

    13 Apr 2026 S1

    110
    Two small drops of liquid of same radius coalesce to form a big drop. The ratio of the total surface energies after and before the change is

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  12. Question 12

    13 Apr 2026 S2

    111
    A spherical drop of liquid splits into 10001000 identical spherical drops. If uiu_i is the surface energy of the original drop and ufu_f is the total surface energy of the resulting drops, the (ignoring evaporation). uf/ui=(10/x)u_f/u_i = (10/x). Then value of xx is

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  13. Question 13

    13 Apr 2026 S2

    110
    Determine the ratio of surface energy of 11 large drop to 11 small drop, if 10001000 small drops combined to form 11 large drop.

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  14. Question 14

    16 Apr 2026 S2

    109
    One thousand small water drops of equal radii combine to form a big drop. The ratio of final surface energy to the total initial surface energy is

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