Question

Give an example of dimensionless quantity but has a unit.

Answer 1

Dimensionless quantity with a unit:

1. Even physical quantities that have no dimensions can at times have a unit.
2. An example of such a quantity is an angle.
3. An angle does not have any dimension since its dimensional formula is $\left[M^0{L}^0{T}^0\right]$.
4. But it has a unit, radians.

Hence, an example of a dimensionless quantity that has a unit is an angle.