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HOW WE USE LIGHT 



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PROBLEM II. WHAT ARE SOME OF THE 

 PROPERTIES OF LIGHT? 



What Happens When Light Meets a Body ? It is inter- 

 esting to play with a beam of light. In a dark room allow 



a small beam of light 

 to pass across the 

 table from a lantern. 

 Make this beam visi- 

 ble by means of dust, 

 smoke, or ammonium 

 chloride fumes. Hold 

 a piece of window 

 glass at right angles 

 to the beam. You 

 can see the beam al- 

 most as brightly back 

 of the glass as in front. 

 This light that comes 

 through is transmitted 

 light. Tilt the glass 

 and you will see a 

 faint beam sent off 

 from the surface. 

 This is reflected light. 

 A still smaller part of 

 the beam is neither 

 transmitted nor re- 

 flected, but is absorbed 

 and changed to heat. 

 Three things happen 

 when a beam of light 



/reflected 



absorbed 



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Explain why the frosted glass has a different 



effect on the light than the window glass does. 



What happens to most of the light that falls upon 



a black body? 



comes to a body that allows light to pass through, but 

 only two things happen when the body does not permit 

 the light to pass through. Can you tell what happens 

 to the light when it meets the latter body ? 



