The dimensional formula for the intensity of radiation is .......

The dimension of $\sqrt{\frac{\mu_0}{\varepsilon_0}}$ is the same as:

Which of the following is not a dimensionless quantity?

The dimensional formula of a physical quantity represented by $\frac{e^2}{4 \pi \varepsilon_0 \hbar}$ is (where $e$ is the charge of an electron,$\varepsilon_0$ is the permittivity of free space,and $\hbar$ is the reduced Planck's constant). Note: The expression $\frac{e^2}{4 \pi \varepsilon_0 \hbar}$ is equivalent to the fine-structure constant $\alpha$ multiplied by the speed of light $c$.

The damping force on an oscillator is directly proportional to the velocity. The units of the constant of proportionality are:

What is the dimension of Luminous flux?