Question

how can i exlpain 'what is a unit and SI unit?' to grade 7 students

Answer 1

Answer:

Units:

Units are standards for measurements of physical quantites. A physical quantity is a quantity that can be in mathematical equations of science and technology. A Unit is a physical quantity, there are seven base quantities (length, mass, time, electric current, temperature, amount of substance and luminous intensity).

SI Units: The international System of units abbreviated as SI Units. (SI stands for Standard Internatianal) and is the set of physical units agreed upon by international convention. The seven base quantities which are mentioned above are very important quantities in SI system and the corresponding units are meter, Kg, second, ampere, Kelvin, mole and candella respectively. All other quantities in SI unit system can be derived from these.

MKS system is a another name for SI unit system.