GENERAL THOUGHT QUESTIONS FOR 

 DISCUSSION AND REVIEW 



GROUP III 



1. Does the sun give us any heat when there are thick clouds overhead? 

 Why? 



2. Why is it hard to walk against the wind? 



3. An explosion occurs within your sight. Do you see the flash before 

 or after you hear the explosion? 



4. If an earthquake occurred in California at 3 P. M., could news of 

 it appear in the 5 P. M. edition of an eastern paper? 



5. Why do the wires strung on telephone poles hum? 



6. Suggest ways in which a chimney adds to health. 



7. Why are there so many lightning strokes without apparent damage? 



8. Why are fuses installed in electric lighting circuits? 



9. Why do all the lights of a one-string Christmas tree set go out if 

 one bulb burns out? 



10. Suggest a reason for keeping bars of steel on the ends of permanent 

 magnets. 



11. Why does wind sometimes prevent sound, but never light, from reach- 

 ing us? 



12. Why does gasoline feel colder on the hand than water? 



13. Why do animals prick up their ears at unexpected sounds ? 



14. Why do we hear an echo distinctly in one spot and perhaps .not at 

 all a few steps away? 



15. Suggest how the noise of an explosion is produced. 



16. Suggest how perspiration reduces one's temperature. 



17. Why are safes that have been through hot fires generally permitted 

 to cool before being opened? 



18. Why is ice in old style icehouses packed in sawdust? 



19. Why do extremely sharp sounds injure the ears? 



20. Is there any advantage in opening the mouth if you are expecting 

 to hear a sharp explosion? Why? 



21. Why does not a pane of glass cast a shadow? 



22. Is it true or false that dark clothing is warmer than light clothing 

 of the same material? Why? 



23. Would a magnet help us to find the proverbial "needle in the hay- 

 stack"? 



24. Why does a clock with a metal pendulum have to be regulated 

 winter and summer? 



25. Why does an image seen through a window sometimes appear distorted ? 

 26r Why are tall steel buildings seldom damaged by lightning? 



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