Radiant Heat and Light 



165 



FIG. 93. Which color is warmest in the sunlight? 



Leave them for about an hour. Now put a thermometer 

 into each to see which is warmest and which is least warm. 



From which bottle has most of the light been reflected 

 back into the air by the cloth around it? Which cloth 

 absorbed most of the light and changed it into heat? Does 

 the colored cloth absorb more or less light than the white 

 one? than the black one? 



(b) On a sunny day when there is snow on the ground, 

 spread three pieces of cotton cloth, all of the same size and 

 thickness, one white, one red or green, and one black, on 

 top of the snow, where the sun shines on them. Watch 

 them for a time. Under which does the snow melt first ? 



