On heating water, bubbles being formed at the bottom of the vessel detach and rise. Take the bubbles to be spheres of radius R and making a circular contact of radius r with the bottom of the vessel. If `rlt ltR` and the surface tension of water is T, value of r just before bubbles detach is: (density of water is `rho_w`) A. `R^(2)sqrt((2rho_(w)g)/(2T))`B. `R^(2)sqrt((rho_(w)g)/(6T)`C. `R^(2)sqrt((rho_(w)g)/(T))`D. `R^(2)sqrt((3rho_(w)g)/(T))`

On heating water, bubbles being formed at the bottom of the vessel det

1.	On heating water, bubbles being formed at the bottom of the vessel detach and rise. Take the bubbles to be spheres of radius R and making a circular contact of radius r with the bottom of the vessel. If `rlt ltR` and the surface tension of water is T, value of r just before bubbles detach is: (density of water is `rho_w`) A. `R^(2)sqrt((2rho_(w)g)/(2T))`B. `R^(2)sqrt((rho_(w)g)/(6T)`C. `R^(2)sqrt((rho_(w)g)/(T))`D. `R^(2)sqrt((3rho_(w)g)/(T))`
Answer» Correct Answer - A The bubble will detach if, `intsinthetaTxxd,=T(2pir)sintheta` Buoyant force `ge` surface tension force `(rho_(w))((4)/(3)piR^(3))ggt(T)(2pir)sintheta` `impliessintheta=(r)/(R)`

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