Question

Collect information about the substances using to reduce the friction in different machines and prepare a report 10to20 line ​

Answer 1

The attachment is your answer.

Answer 2

   Friction can be reduced by making the surface smooth by polishing.slide in the park is polished to make its surface smooth and reduce friction.Due to reduced friction of a polished,smooth slide,children can slide down easily.

  Friction can be reduced by applying lubricants(like oil , grease,graphite or fine powder) to the rubbing surface.When oil or grease is applied to moving parts of a machine ,then their surfaces do not rub directly aganist each other, they rub through a layer of oil and grease.

  Friction can be reduced by using wheels to move objects.If this heavy suitcase is fitted with small wheels then it can pulled very easily.Because when we attached wheels then sliding friction is converted into rolling friction.

   And rolling friction between the wheels of suitcase and ground is much less.Friction can be reduced by attaching wheels to move the objects.

     Friction can be reduced by using ball bearing between the moving parts of machine.Ball bearing is a device which consists of a ball bearing can roll freely.When the wheels revolves the balls of ball bearing roll and reduce friction.