undamental quantities are the basis of
all measurement. In the SI system or international system of measurement there
are seven fundamental units.

QUANTITY

UNITS

Length (l)

Meters

Mass
(m)

Kilogram

Time
(t)

Seconds

Temperature
(T)

Amperes

Current
(c)

Kelvins

Amount
of substance

Mole

Luminous
intensity

Candela

 

 All other things that we measure are derived
from these units; it means that we have to use these units in some combination
to describe anything else that we wish to measure.  For example, speed is a combination of time and
distance that will be measured. Derived quantities are those physical
quantities that are derived from the combination of fundamental quantities.

2)         Benefits of
having units to all the physical quantities.

Without units, it would be complex
for anyone to express and compare measured values in a meaningful way. SI
system of units is known as the International System of Units. Quantities only
have meaning if we know what one is measuring them in. for example if a person records
“10” as opposed to “10 kg”, then the first recording makes no sense to us because
we can take that 10 to mean anything but by adding the unit of kg to the value,
we understand it is weigh that we are dealing with. Units are used to distinguish
between quantities.

3)         Why is it
important to measure the physical quantities?

            Measurement
is the act of comparing a physical quantity with its unit. Something is only meaningful
when we are able to measure and express it with certain units and proportions. Without
measurement of a quantity, how else would we know the value or importance of it?
Let us take for example time. This quantity is only meaningful because it can be
measured with an instrument known as a clock and can be expressed with certain units
whether it is seconds or minutes etc. having a physical quantity without measurement
really doesn’t serve a purpose to us unless we can add some sort of value to the
quantity.