6A02.15 - Straight Line Propagation of Light
Hold the ball or globe between the point source and the screen. Observe how the shadow size changes as you move the ball closer or farther away from the screen.
- Maja Poklinek Cancula, Mojca Cepic, "A Spreading Shadow In Color", TPT, Vol. 55, #9, Dec. 2017, p. 586.
- Chris Goedde, "Leaping Shadow", TPT, Vol. 49, # 5, May 2011, p. 318.
- Janice VanCleave, "92, How Light Travels", Teaching the Fun of Physics, p. 139.
- Janice VanCleave, "93, What Makes Shadows?", Teaching the Fun of Physics, p. 140.
- Sara Stein, "Where Shadows Fall", The Science Book, p. 199.
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