The structure and the importance of the levers

 

The levers are very important in our life to perform tasks more easily .

The levers are the most common simple machines which they help man to perform heavy tasks easily . They were first described in 260 B.C .

 

The liver is affected by an effort force and a resistance force , and  It is a rigid bar ( straight or curved ) that rotate around a fixed point called fulcrum .

 

The structure of the lever 

The liver consists of :

 

1. A resistance force which is the force that resulted from the weight of the body that we want to move .

    

2. An effort force which is the force that exerted by a person to equilibrate  the resistance . 

    

3. The fulcrum which is a fixed point , where the bar rotates around .

   

   The lever consists of a resistance force , an effort force and fulcrum .

Examples on levers  

 

Stapler , Manual broom , Crowbar , Seesaw , Scissors , Bottle opener , Nutcracker , Ice or sweet holder and Wheelbarrow .

 

The importance of levers 

 

1. The levers increase the force because they save the exerted effort by using a small force to make a great effort as moving a heavy load . 

    

   Examples : crowbar , bottle ( soda water ) opener , nutcracker and wheel barrow .

   

   The wheelbarrow carry heavy objects by doing a small force .

    

2. They increase the distance  , where some levers allow the exerting force for a small distance to move an object for a longer distance .

    

    Examples : The manual broom , If your hand moves a small distance at the upper part of the manual broom , the lower part will move a longer distance .

    

3. They avoid dangers as they are used to pick up the hot , cold and poisonous materials . Examples : Ice holder and coal holder ( coal tongs ) .

   

   The coal tongs are used to avoid dangers .

    

4. They increase the speed of the objects that we affect on  

    

   Examples : Hockey bat .

   

   Hockey bat is used to increase the speed of objects that we affect on .

    

5. They move force from one place to another . 

    

   Examples : The force of your hand on the manual broom moves from one place to another to collect the garbage without bending .

    

6. They have the accuracy in performance as they are used to pick up very small object . 

    

   Example : Tweezers .

   

   The tweezers are accurate levers in performance .