======Door Knobs and Handles======


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**Alternative titles:** Door Handle as a Lever
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====Summary====                   
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====Procedure====  
  - Identify the fulcrum: Show students that the spindle inside the door knob/handle acts as the pivot point.  
  - Apply effort: Push down on the lever handle or twist the knob.  
  - Show the load: Explain that the latch is the part resisting movement.  
  - Retract the latch: Demonstrate how turning the spindle retracts the latch bolt from the strike plate.  
  - Open the door: With the latch retracted, push or pull the door to open it.  
  - Review the parts of the lever: Effort (your hand force), Fulcrum (spindle), and Load (latch mechanism).



====Links==== 
  * None available

====Variations====
  * Compare a lever-style handle to a round knob, showing differences in motion (push/pull vs. twist).  
  * Demonstrate how a classroom lock allows the key to control the lever, adding a real-world application.  
  * Ask students to think of other levers in daily life (scissors, bottle openers, pliers).



====Safety Precautions====
  * Ensure the door or demonstration setup is stable and won’t tip over.  
  * Supervise younger students to prevent pinched fingers in the latch mechanism.




====Questions to Consider====
  * How does the handle make it easier to retract the latch compared to pushing directly on the latch? (The handle provides leverage, spreading force over distance.)  
  * Why is a lever handle easier for some people to use than a round knob? (Less grip strength is required to push a lever compared to twisting a knob.)  
  * What are the effort, fulcrum, and load in this demonstration? (Effort = hand force, Fulcrum = spindle, Load = latch mechanism.)