NTA Abhyas JEE Main2020PhysicsUnits and DimensionsPractice
If the time period ( T ) of vibration of a liquid drop depends on surface tension ( S ) , radius ( r ) of the drop and density ( ρ ) of the liquid, then the expression of T is
Options
- AT = k ρ r 3 / S
- BT = k ρ 1 / 2 r 3 / S
- CT = k ρ r 3 / S 1 / 2
- DNone of these
Correct answer
A. T = k ρ r 3 / S
Step-by-step solution
Let T ∝ S x r y ρ z by substituting the dimension of [ T ] = [ T ] [ S ] = [ M T − 2 ] , [ r ] = [ L ] , [ ρ ] = [ M L − 3 ] and by comparing the power of both the sides x = − 1 / 2 , y = 3 / 2 , z = 1 / 2 so T ∝ ρ r 3 / S ⇒ T = k ρ r 3 S