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Mechanical properties of matter

               ICT corner

                           Visit https://phet.colorado.edu and select the simulation titled Density
                           and Buoyancy to help students visualise and demonstrate the concept
                           of density of a substance.



           .Chapter summary
             1.  Elasticity is the ability of a deformed material to regain its original size and shape
                after the deforming force is removed.
             2.  Hooke’s law states that ‘provided that the elastic limit is not exceeded, the extension
                of elastic material is directly proportional to the force applied’.
             3.  Surface tension is the ability of the surface of a liquid to behave like a fully
                stretched elastic skin. This elastic nature of the surface of a liquid is caused by
                the attraction of the liquid molecules at the surface.
             4.  Capillarity is the tendency of a liquid to rise and fall in narrow tubes or to be drawn
                into small openings. It occurs when the adhesive forces between the liquid and the
                walls of the tube are larger than the cohesive forces between the liquid molecules.


                 Revision exercise 6                       (a)  between O and P      (b) at P

             Section A                                     (c)  between P and Q      (d) at Q

             1.   Answer all questions by writing the   (ii) When a force is applied to a given
                letter of the most correct answer          material, the material returns to its
             (i)  Where on the graph is the limit of       original shape after the  force is
                proportionality for an elastic solid?      removed. This behaviour is termed as:
                                                           (a)  Plastic deformation
                                                           (b)  Elastic deformation
                                       Q
                                                           (c)  Irreversible deformation
                                                           (d)  Viscous deformation
              Extension (m)                                a beaker of water. The water level
                                                       (iii) A glass capillary tube is placed in


                                                           inside the tube is higher than the
                                   P
                                                           water level outside due to:
                                                           (a)  Cohesion   (c) Surface tension
                                                           (b)  Adhesion   (d) Elasticity
                                                        (iv) A weight of 2.0 N is hung from a
                                                           spring. The extension produced is
                                                           6.0 cm. The 2.0 N weight is removed
             O
                                  Load (N)
                                                           and an 8.0 N weight is hung from the
                          Figure 6.17                      spring. The spring does not pass its


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     Physics Form 1 Final.indd   133                                                        16/10/2024   20:57
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