CONVECTION 99 



6. When the sun shines on a section of country, what effect is it likely 

 to have on the movement of the air there? 



6. Do you infer that the wind blows from a single direction or from 

 all directions toward a column of rising air? 



7. When the wind blows from the north, in what direction is the 

 nearest column of rising air? 



8. Where is it when the wind blows from the east? 



9. How do you explain the statement that the Gulf States help to 

 warm Chicago? 



10. On a weather map the areas marked "High" are regions of heavy 

 air and those marked " Low " are regions of lighter air. In what direction 

 should the air near the ground move, from a high to the nearest low or the 

 reverse? 



11. In what direction should the elevated currents connecting a high 

 and a low flow? 



12. Why does blowing a hot liquid cool it? 



13. On a cold day, why does it seem so much colder in the wind than 

 in a sheltered situation (83)? 



14. How does an open fireplace ventilate a room? 



16. Which would be more effective in ventilating a room, opening a 

 window at the top or bottom, or opening it at the top and bottom? 

 Why? 



16. Why does not the carbon dioxide produced by a flame extinguish it? 



