Question

A big drop is formed by coalescing 1000 small droplets of water. The surface energy will become ______.

Options

• `1/100`th

• `1/10`th

• 100 times

• 10 times

Answer 1

A big drop is formed by coalescing 1000 small droplets of water. The surface energy will become 10 times.

Explanation:

We have, h = `(2 T cos theta)/(r rho g)`

Mass of the water in the capillary (m) = ρV

= `rho xx pi r^2 xx (2 T cos theta)/(r rho g)`

⇒ m ∝ r

∴ `m_1/m_2 - r/(2r)`

or m₂ = 2m₁

= 2M