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MHT CET 2026 (15 May, Shift 1) · Excess Pressure: Drops & Bubbles

Excess Pressure: Drops & Bubbles question from MHT CET 2026 (15 May, Shift 1)

Q1MHT CET 2026 · 15 MAY · SHIFT 1Easy

Excess Pressure: Drops & Bubbles

A water drop is divided into 8 equal droplets. The pressure difference between the inner and outer side of the big drop will be

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Answer: (b)

  1. Volume conserved: 43πR3=8⋅43πr3⇒R=2r\frac{4}{3}\pi R^3 = 8 \cdot \frac{4}{3}\pi r^3 \Rightarrow R = 2r.
  2. Excess pressure in a drop ΔP=2TR\Delta P = \frac{2T}{R}, so ΔP∝1R\Delta P \propto \frac{1}{R}.
  3. ΔPbigΔPsmall=rR=12\frac{\Delta P_{big}}{\Delta P_{small}} = \frac{r}{R} = \frac{1}{2}
  4. So the answer is (b) half of that for a smaller droplet.
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