If energy E, velocity V and time T are taken as fundamental units, the dimensional formula for surface tension is

Explanation

Surface Tension , S , `= MT^(-2)`
Energy , E`= ML^2 T^2 `, velocity , `v = LT^(-1) , ` Time , `t=T^1`
`therefore S , alpha (E)^a (v)^b (t)^c and `
`MT^(-2) = (ML^2 T^(-2))^a (LT^(-1)) (T)^c`
Comparing power of M , L nd T on either side
a=1 , 2a+b = 0 `implies c=-2`
`therefore S. = E^1 (V)^(-2) (T)^(-2)`