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3.  The salesman is measuring the _____________ of petrol. (length/capacity)

           4.  The doctor is measuring the _____________ of the patient. (temperature/weight)

           5.  The boy is measuring an _____________ in his wrist watch. (length/time)




          What is Measurement?
          To  find  the  length,  width,  height,  time,  area,  volume,  etc.,  of  things  is  known  as

          measurement.



           H istory of Measurement

          In earlier days, people used their body
          parts, such as cubit (approximately equal
          to 20 inches or 50 centimetres), handspan,

          pace and foot as measuring devices. Mass,
          time, temperature, capacity were measured
          by natural objects.
                                                                Hand Span                          1 Foot


          Activity 14.1

          Compare your hand span and thumb size with your friend’s and parents’ and find out whether
          yours is bigger, smaller or the same.

          Fill the table with your observations.

                   You              Hand span               Pace                Thumb                 Cubit

              Your friend

             Your parents



          From the above activity, you will find that size of body parts is not same and hence,
          measurements taken using them will be different. The reason is clear that the size of
          body parts varies from person to person. This does not give accurate results.

          Scientists made up their mind to prepare                       Factual Study
          a standard measuring unit which might

          be accepted throughout the world. This                         In United States, people do not
                                                                         use inches, feet, yards or miles for
          led  to  determine  a  unit  (fixed  standard)                 measurement. They use the customary
          for measurement. Fixed units are now                           units of measurement. They use ounces
          available for measurement of area,                             and pounds for measuring weight.
          temperature,  volume,  time,  length,  width                   Volume is measured in cups, pints,
          and capacity and mass.                                         quarts and gallons.


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