Question

a mercury drop of radius 1 cm is sprayed into 10^6 droplets of equal size. calculate energy expended. surface tension of mercury = 32× 10^-2 N/m​

Answer 1

A mercury drop of radius 1 cm is sprayed into 10^6 droplets of equal size, the surface tension of mercury = 32× 10^-2 N/m​. Calculate the energy expended.

Explanation:

• From the above-given data, Let us consider 'R' as the radius of the big drop, and 'r' as the radius of the small drop.
• The total volume is conserved on the formation of small drops.

• Solution:  4/3 πr³ × $10^{6}$ = 4/3 πR³

• The other form is ⇒ r = R × $10^{-2}$ = 0.01 cm

• To calculate the energy expended, the formula is

Energy expended = Surface tension × Increase in surface area

                              = T × 4π(R² - $10^{6}$ r²)

                              = 32 ×  $10^{-2}$ × 4 × 3.14 [ $10^{6}$(0.01 × $10^{-2}$) - ($10^{-2}$)²]

                              = 401.92 × $10^{6}$ × $10^{4}$ J