Q.Which SI unit is used to measure luminous intensity?

A physical quantity is what is measured (e.g. mass, density); a unit is what it is measured IN (e.g. kilogram). Kilogram is a unit, not a quantity.

• Kilogram: this is the SI unit of mass — not a quantity itself.
• Density: a physical quantity (mass per unit volume). …

Candela (cd) is the SI base unit for luminous intensity, one of the seven fundamental SI units.

The seven SI base quantities and their units are: length (metre), mass (kilogram), time (second), electric current (ampere), thermodynamic temperature (kelvin), amount of substance (mole), and luminous intensity (candela).

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A physical quantity is WHAT is measured (e.g. mass); a unit is the standard used to measure it (e.g. kilogram). Kilogram is a unit, not a quantity.

Time, Mass, and Impulse are all physical quantities -- they describe measurable properties of the physical world and each has its own dimensional formula ([T], [M], [MLT^-1] respectively). Kilogram, by contrast, is the SI unit in which t …