======Angle of Sunlight and Energy Distribution======


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**Alternative titles:** Investigating the Effect of Sun Angle on Heating
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====Summary====                   
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====Procedure====  
  -Gather materials: flashlight, grid paper, protractor, pencil, tape, and several books.  
  -Tape a sheet of grid paper to the cover of a book so it stands vertically.  
  -Stack books on a table and place the flashlight on top to elevate it.  
  -Turn off room lights to create a dark environment.  
  -Position the flashlight so its beam shines directly (90°) onto the grid paper.  
  -Trace the illuminated circle on the paper with a pencil and count the number of grid squares lit by the light, estimating partial squares if needed.  
  -Repeat the experiment with the flashlight tilted at different angles (e.g., 45° and 30°).  
  -For each angle, trace the illuminated shape and count the number of squares covered.  
  -Record observations for each angle.



====Links==== 
Angle of insolation lab - Urfsigns Schweizer: 
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====Variations====
  *Use a light sensor or thermometer to measure actual light intensity or temperature differences at each angle.  
  *Try more angles (15°, 60°, etc.) for a complete data set.  
  *Compare results using different light sources or distances from the paper.  
  *Graph lighted area (in squares) versus angle to visualize the relationship.



====Safety Precautions====
  *Avoid shining the flashlight directly into anyone’s eyes.
  *Supervise students while working in the dark to prevent tripping or equipment damage.




====Questions to Consider====
  *How does the shape of the illuminated area change as the angle decreases? (It becomes larger and more stretched out.)  
  *Why does the 90° angle create a more intense light spot? (The same amount of light energy is focused on a smaller area.)  
  *What does this model tell us about sunlight at the equator versus the poles? (Sunlight at the equator is more direct and concentrated, producing higher temperatures; sunlight near the poles is angled and spread out, resulting in cooler temperatures.)  
  *How does this experiment relate to Earth’s seasons? (As Earth tilts, the Sun’s rays strike at different angles throughout the year, causing seasonal temperature changes.)  
  *How might this concept affect solar panel efficiency? (Panels work best when positioned to receive light as directly as possible.)