Question

Check the correctness of the relation `h =(2 sigma cos theta)/(r^2 dg),` where h is height , `sigam` is surface tension, `theta` is angle of contact, r is radius, d is density and g in acceleration due to gravity.

Answer 1

Correct Answer - wrong
`LHS = [L]`
`RHS = (2sigma cos theta)/(r^2dg) = (MT^(-2))/(L^2(ML^(-3)(LT^(-2))`
`(therefore 2 cos "theta has no dimension")`
`= [ M^(0)L^(0)T^(0)]`
AS `LHS != RHS,` therefore, formula is wrong.