We use Optical Character Recognition (OCR) during our scanning and processing workflow to make the content of each page searchable. You can view the automatically generated text below as well as copy and paste individual pieces of text to quote in your own work.
Text recognition is never 100% accurate. Many parts of the scanned page may not be reflected in the OCR text output, including: images, page layout, certain fonts or handwriting.
THE LIGHT SOURCE
1. What two light sources are employed in projection:
2. Is there a wide variation in available arc light sources?
3. Is special treatment of each arc light source essential to best results ? JZZT/
4. How is an electric arc formed ?
5. What becomes of the carbon particles ?
6. How is a conductor of high resistance established between the incandescent carbon tips ?
7. What is the "crater" of an electric arc? How is it formed ?
8. What is the temperature of the crater floor?
9. How does an electric arc crater floor compare in brilliancy with other light sources?
10. What substance will withstand the highest temperature before being transformed into a gas? i w .
1 1 . Why will no current flow until the carbon tips are in actual physical contact?
12. Why will current flow after the carbons are again separated ?
Illumination Values, page 358
13. How does the illumination of an .electric arc crater compare with its brilliancy and area?
14. What is the approximate brilliancy of the old style straight no**arc per square mm of crater floor area? Of the low in 7-Td tensity arc? Of the reflector type high intensity arc? Of /3o ^6 the straight high intensity arc? Of the old style a.c. arc?
Of the new style high intensity a.c. arc? Of the new nonrotating high intensity d.c. arc? 1 5. How would you calculate the total light producing po)ver,of
an electric arc?./^6ii^ -y ■ t , * . «***/ h <&*'"/**?* ^*^rl6. How is the total candle power of a crater floor calculated?
17. Why is a core necessary in the positive carbon of a d.c. ./ arc ? In both carbons of an a.c. arc ?
18. What is the depth of the incandescent film on a crater floor
19. Why is the very thin depth of the incandescent film on the crater floor an argument against under-loading carbons?
• 347