Suppose you have taken a dilute solution of oleic acid in such a way that its concentration becomes 0.01 cm3 of oleic acid per cm3 of the solution. Then you make a thin film of this solution (monomolecular thickness) of area 4 cm2 by considering 100 spherical drops of radius ${\left( {{3 \over {40\pi }}} \right)^{{1 \over 3}}} \times {10^{ - 3}}$ cm. Then the thickness of oleic acid layer will be x $\times$ 10$-$14 m. Where x is ____________.
Answer (integer)
25
Solution
4t<sub>T</sub> = 100 $\times$ ${4 \over 3}\pi {r^3}$
<br><br>= $100 \times {4 \over 3}\pi \times {3 \over {40\pi }} \times {10^{ - 9}}$
<br><br>= 10<sup>-8</sup> cm<sup>3</sup>
<br><br>$\Rightarrow$ t<sub>T</sub> = 25 $\times$ 10<sup>-10</sup> cm
<br><br>= 25 $\times$ 10<sup>-12</sup> m
<br><br>t<sub>0</sub> = 0.01 t<sub>T</sub> = 25 $\times$ 10<sup>-14</sup> m
<br><br>$\therefore$ x = 25
About this question
Subject: Physics · Chapter: Properties of Solids and Liquids · Topic: Elasticity
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