Page 95 - Primary Five Science
P. 95

Weight and Mass





         .
         Weight
         The force exerted on a body by gravity. This is often expressed

         in the formula W = mg, where W is the weight, m the mass of

         the object, and g gravitational acceleration.
         .

         The weight of an object is determined by the following;

         1. The pull of the force of gravity

         2. Size of the object

         3. Material from which an object is made
         The basic unit for weight is Newton (N).
         .

         Mass

         This is the quantity of matter in an object.

         Mass is constant.  The mass of a given object

         The units for mass are grams (g) or kilograms (kg). Weight and

         mass are both measured using the following instruments.





         Mass                                                  Weight

         Mass is constant (does not                            Weight changes on different


         change )                                              planets (because there’s dif-


                                                               ferent gravity on different

                                                               planets)


         Mass is measured in grams                             Weight is measured in New-


         (g)                                                   ton (N)

         Mass is a mount of matter in                          Weight is force due to gravity

         an object
   90   91   92   93   94   95   96   97   98   99   100