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n drops of a liquid, each with surface e...

n drops of a liquid, each with surface energy E. joining to form a single drop
(a). Some energy will be released in the process
(b). Some energy will be absorbed in the process
(c). The energy released or absorbed will be `E(n-n^(2//3))`
(d). the energy released or absorbed will be `nE(2^(2//3)-1)`

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To solve the problem of n drops of a liquid each with surface energy E joining to form a single drop, we can follow these steps: ### Step 1: Understand the Problem We have n small drops, each with a surface energy E. When these drops coalesce to form a single larger drop, we need to analyze the change in surface energy. ### Step 2: Calculate the Volume The volume of each small drop is given by: \[ V_{small} = \frac{4}{3} \pi r^3 \] Thus, for n small drops, the total volume is: \[ V_{total} = n \cdot V_{small} = n \cdot \frac{4}{3} \pi r^3 \] When these drops combine into a single larger drop, the volume of the larger drop (with radius R) is: \[ V_{large} = \frac{4}{3} \pi R^3 \] Setting the two volumes equal gives: \[ n \cdot \frac{4}{3} \pi r^3 = \frac{4}{3} \pi R^3 \] From this, we can simplify to find: \[ R^3 = n \cdot r^3 \] Thus: \[ R = n^{1/3} r \] ### Step 3: Calculate Initial Surface Energy The surface energy of a single small drop is: \[ E = 4 \pi r^2 T \] Therefore, the total initial surface energy of n small drops is: \[ E_{initial} = n \cdot E = n \cdot (4 \pi r^2 T) = 4 \pi n r^2 T \] ### Step 4: Calculate Final Surface Energy The surface energy of the larger drop is: \[ E' = 4 \pi R^2 T \] Substituting R from Step 2: \[ E' = 4 \pi (n^{1/3} r)^2 T = 4 \pi n^{2/3} r^2 T \] ### Step 5: Compare Initial and Final Surface Energies Now, we compare the initial and final surface energies: - Initial energy: \( E_{initial} = 4 \pi n r^2 T \) - Final energy: \( E' = 4 \pi n^{2/3} r^2 T \) ### Step 6: Calculate Energy Released The energy released during the coalescence process is given by: \[ Q = E_{initial} - E' \] Substituting the expressions we found: \[ Q = 4 \pi n r^2 T - 4 \pi n^{2/3} r^2 T \] Factoring out common terms: \[ Q = 4 \pi r^2 T (n - n^{2/3}) \] ### Step 7: Relate to Given Options The energy released can be expressed in terms of E: Since \( E = 4 \pi r^2 T \), we can rewrite the released energy as: \[ Q = E(n - n^{2/3}) \] ### Conclusion The correct answer is that some energy will be released in the process, and the energy released is given by: \[ Q = E(n - n^{2/3}) \] Thus, the correct option is (c). ---

To solve the problem of n drops of a liquid each with surface energy E joining to form a single drop, we can follow these steps: ### Step 1: Understand the Problem We have n small drops, each with a surface energy E. When these drops coalesce to form a single larger drop, we need to analyze the change in surface energy. ### Step 2: Calculate the Volume The volume of each small drop is given by: \[ V_{small} = \frac{4}{3} \pi r^3 \] ...
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