Question

how many types of unit are there? write their definition.​

Answer 1

Answer:

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Explanation:

There are seven basic units in the SI system: the meter (m), the kilogram (kg), the second (s), the kelvin (K), the ampere (A), the mole (mol), and the candela (cd).

Answer 2

Answer:

There are seven basic units in the SI system: the meter (m), the kilogram (kg), the second (s), the kelvin (K), the ampere (A), the mole (mol), and the candela (cd).

Meter : SI Unit of length, A device that measures and records the quantity, degree, or rate of something.

Kilogram : The SI unit of mass (equivalent to approximately 2.205 lb), first introduced as a unit of mass for the metric system.

Second : It is the SI unit of time. It is defined by taking the fixed numerical value of the caesium frequency ΔνCs, the unperturbed ground-state hyperfine transition frequency of the caesium-133 atom, to be 9 192 631 770 when expressed in the unit Hz, which is equal to s–1.

Kelvin : The kelvin (abbreviation K), less commonly called the degree Kelvin (symbol, o K), is the SI unit of thermodynamic temperature. A temperature of 0 K represents absolute zero, the absence of all heat.

Ampere : The ampere is the SI unit of electric current. The ampere, or 'amp' for short, measures electric current, which is a flow of electrons along a wire or ions in an electrolyte, as in batteries. Electric current allows us to power electrical devices, like smartphones or laptops and can even be used to operate a bus or car

Mol : The mole, symbol mol, is the SI unit of amount of substance. One mole contains exactly 6.022 140 76 x 1023 elementary entities. This number is the fixed numerical value of the Avogadro constant, NA, when expressed in the unit mol–1 and is called the Avogadro number.

Candela : The candela is the SI unit of luminous intensity. The candela is used to measure the visual intensity of light sources, like light bulbs or the bulbs in torches. It is the only SI base unit based on human perception.

Explanation:

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