CameraIcon
CameraIcon
SearchIcon
MyQuestionIcon


Question

A. liquid drop of radius ‘R’ breaks into 64 tiny droplets each of radius ‘r’. If the surface tension of the liquid is ‘T’ then gain in energy is:


A
48πR2T
loader
B
12πr2T
loader
C
96πr2T
loader
D
192πr2T
loader

Solution

The correct option is C $$192\pi r^{2}T$$
Let the density of the liquid be  $$\rho$$.
Mass of the liquid drops must be equal to the total mass of the droplets.
$$\therefore$$   $$\rho \times \dfrac{4\pi}{3}R^3  = 64 \times \rho \times \dfrac{4\pi}{3} r^3$$            $$\implies R =4r$$

Change in surface area   $$\Delta A  = 64 \times 4\pi r^2  - 4\pi R^2$$
$$\therefore$$    $$\Delta A  = 64 \times 4\pi \times r^2 - 4\pi (4r)^2  =192 \pi r^2  $$
$$\therefore$$ Gain in energy      $$E  = T \Delta A  = 192 \pi r^2 T$$

Physics

Suggest Corrections
thumbs-up
 
0


similar_icon
Similar questions
View More


similar_icon
People also searched for
View More



footer-image