FORCE AND ENERGY (CLASS 5)

FORCE

       FORCE IS A PUSH OR PULL OF A BODY.

                 e.g pushing and pulling of a table.

          EFFECTS OF FORCE

                     1.FORCE CAN MAKE A STATIONARY BODY MOVE .e.g. moving a table

                            2.FORCE CAN CHANGE THE SHAPE OF THE

OBJECT.e,g using  a paper   to make a ball

                                    3.FORCE CAN STOP A MOVING BODY .e.g  a

boy running and being stopped by his friend

                                                4.FORCE CAN CHANGE THE DIRECTION

OF A MOVING OBJECT .e.g  while batting the balls goes in all the direction

UNIT OF FORCE:

Force is a physical quantity that can be measured. The SI unit of force newton,whose symbol is N.

TYPES OF FORCES

1.Contact force- The force produced through contact.

Very important contact force is frictional force.

2.Field force-When two objects interact without touching each other.

                                        A . Magnetic force –The force produced

through a magnet. e.g.use magnet  to attract the nails.

                          B. Gravitational force- The force produced by the

gravitational pull of the earth. E.g  you throw a ball up in the air it comes down.

                C. Electrostatic force –The force produced  by the electrostatic, by getting a body charged.. E.g a tiny bits of paper,rub the

 plastic ruler   on your hair. The ruler gets charged and it attracts

the paper  to it.

D.Muscular force- The force produced by muscles.e.g lifting of a stone

Assignments:

a.What is force? Write the SI unit of force.

  

b. What is contact force?

c.Define gravitational force.