A film of soap solution is formed between two straight parallel wires of length $$10 \mathrm{~cm}$$ each separated by $$0.5 \mathrm{~cm}$$. If their separation is increased by $$1 \mathrm{~mm}$$ while still maintaining their parallelism. How much work will have to be done?
(surface tension of solution $$=65 \times 10^{-2} \mathrm{~N} / \mathrm{m}$$ )
A soap bubble of radius '$$R$$' is blown. After heating a solution, a second bubble of radius '$$2 \mathrm{R}$$' is blown. The work required to blow the $$2^{\text {nd }}$$ bubble in comparison to that required for the $$1^{\text {st }}$$ bubble is
A fluid of density '$$\rho$$' and viscosity '$$\eta$$' is flowing through a pipe of diameter '$$d$$', with a velocity '$$v$$'. Reynold number is
Water is flowing through a horizontal pipe in stream line flow. At the narrowest part of the pipe