Question

Quantitative measurement of properties is required for scientific investigation. Earlier, two different systems of measurement, i.e., the English System and the Metric System were being used in different parts of the world. The metric system, which originated in France in late eighteenth century. The SI system has seven base units. | Base Physical Quantities | Unit | |--------------------------|------| | 1. Length | Metre – m | | 2. Mass | Kilogram – kg | | 3. Time | Second – s | | 4. Electric current | Ampere- A | | 5. Thermodynamic Temperature | Kelvin – K | | 6. Amount of substance | Mole – mol | | 7. Luminous intensity | Candela- cd | Mass of a substance is the amount of matter present in it, while weight is the force exerted by gravity on an object. Density of a substance is its amount of mass per unit volume. The mole, symbol mol, is the SI unit of amount of substance. One mole contains exactly 6.02214076 × 10²³ elementary entities. This number is the fixed numerical value of the Avogadro constant, NA, when expressed in the unit per mol and is called the Avogadro number. There are three common scales to measure temperature — °C (degree celsius), °F (degree fahrenheit) and K (kelvin). The temperatures on two scales are related to each other by the following relationship: °F = 9/5 (°C) + 32 The kelvin scale is related to celsius scale as follows: K = °C + 273.15

Is the SI unit of Luminous Intensity?

The prefix 10⁹ is