The advantage and the disadvantage of friction and the ways to decrease the friction

The friction force helps us to walk  .

Do you know what is the meaning of the friction ?

 

You should know that the friction force is the force exists between  the two  surfaces when they touch each other and it affects in the opposite direction of the movement . 

 

There are different types of the friction as the friction between the bodies and the air , the friction between the solids , and the friction between the bodies and the water .

The resistance air is affected by the body's speed and the surface area of the body .

What are the factors affecting the friction force ?

The friction force increases by increasing the body surface area .

1. The surface area of the moving object .

    

2. The body's speed .

    

3. The type of the material surface .

    

   

   The friction force occurs when there is a contact between two surfaces .

The disadvantage of the friction

 

You should know that the friction causes the damage to the most of the machines as it raises the temperature of the internal moving parts of the machines to more than a certain extent , So the machines are damaged , and a lot of money is wasted .

 

What are the ways to decrease the friction force ? 

 

• You should use the lubricants and the oil in the machines to form a thin layer between the internal moving parts of the machines to reduce the effect of the friction force . 

   

  Example : Using The lubricants and the oil in the car engines .

   

• You should use The ball bearing in the machines . They are formed of a group of small metallic balls which have smooth surface , So the friction between them is almost non existent . 

   

  Example : The ball bearing that exists in the axis of the car engine , and it transmits the motion from the car engine to the wheels .

   

  The advantage of the friction

   

     

  

  Lighting of a match is from the advantages of the friction .

• The friction force helps in moving and stopping the cars or the bicycles , It helps in lighting of match

    
  

  

   

• The friction force is very important in controlling the car speed and  changing the car direction .

   

• It helps us to walk as the friction force between the ground and our shoes prevents us from slipping down .

   

 The life applications of the friction

 

• You should replace the car tires , when their grooves disappear , Because they are necessary to squeeze  the water out , The water reduces the friction and make the control of the car very hard .

   

• You should know that the air resistance is also a friction force resulting from the movement of solid objects through the air .

   

  You should not increase the car speed up to a certain limit to reduce the air resistance , and the consumption of the fuel .

   

• To decrease the air resistance ,The rockets , the aircrafts and the trains should be designed in streamline shapes , Also the bodies of the birds have streamline shapes .

  

  The train is designed in streamline shape to decrease the air resistance .

• Parachutist should open the parachute to land safely .

   

• Birds stretch their wings on landing to decease their speed on landing .

   

• You should know that the water resistance is also a friction force resulting from the movement of any object through the water . To decrease the water resistance , The ships are designed in streamline shapes , Also fish have streamline shapes .

 

The water resistance is affected by the body's speed and the surface area of the body .