Page 40 - full
P. 40

Types of Forces

Muscular Force                                                A boy pushing box
Force that is applied by our muscles is called as muscular
force. When we push, pull or lift anything, we apply
muscular force.

                         Gravitational Force
                         It is the force by which earth pulls anything towards itself.
                         We stay on the ground due to gravitational force. A fruit
                         falls from the tree on the ground due to gravitational force.

Fruit falling from tree

Frictional Force
A rolling ball stops due to the force of friction. This force slows
down a moving object. We are able to walk because of the
frictional force. Vehicles are stop due to the frictional force. It is
also called force of resistance.

                                                                                                  Frictional force

                     Elastic Force
                     When we strength a spring, it increases its length. But when we
                     release, it regains its original position. This is due to elastic force.

                Mechanical Force
                Simple machines work on mechanical force.
    Gulel For example, a pair of scissors uses this force
                to cut something. This force save our energy
                and time.

                                                                             Girl cutting cloth

                         Buoyant Force                                       with scissors

                         If we push down a ball floating on water, we feel an upward

                         thrust. This feel or push is called buoyant force.

Ball in a water tub

44
   35   36   37   38   39   40   41   42   43   44   45