# Physics for Technical Students in Colleges and Universities

List price: US\$40.33

Currently unavailable

AbeBooks may have this title (opens in new window).

## Description

This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1921 edition. Excerpt: ...be substituted for 0, and V', then the velocity of light v will be found to be approximately 186,000 mi. per second. It is interesting to note that if the velocity of light V, as found by means of some other method, were substituted in Eq. 104, the velocity V' of the earth in its orbit could be determined. Multiplying this value by the number of seconds in a year would give the circumference of the earth's orbit, from which its radius, i.e., the distance from the earth to the sun, could at once be found. 289. Velocity of Light, Fizeau's Method.--In 1849, H. L. Fizeau (1819-96), by an ingenious arrangement of apparatus, which we shall not discuss in detail, made a determination of the velocity of light in air. Imagine an observer to be near a source which is sending a narrow beam of parallel light to a mirror about 5.4 miles distant, the mirror being so arranged as to reflect the light back to the observer. If, now, a toothed wheel similar to the cog wheels of a clock, only much larger, is placed with its axis parallel to the beam of light, in such a position that the beam both going and returning passes through the space between teeth or cogs, then the observer will see the reflected light from the distant mirror. If, however, the wheel is rotated at such a speed that while the light is traveling to the distant mirror and back (11 miles) the wheel turns a distance equal to one half the distance between cogs, then the returning beam will be intercepted by a cog and will, therefore, not reach the observer. Obviously, under these circumstances, the time T2 required by the light to travel the distance 2L, i.e., to the mirror and back, is equal to T1, the time required for the rim of the wheel to travel the interval...show more

## Product details

• Paperback | 282 pages
• 189 x 246 x 15mm | 508g
• United States
• English
• black & white illustrations
• 1236954637
• 9781236954633