 | Henry Smith Carhart, Horatio Nelson Chute - Physics - 1892 - 400 pages
...be inversely as 1 : 4 : 9 ; but 1, 4, and 9 are the squares of 1, 2, and 3 respectively. Therefore, the intensity of the illumination varies inversely as the square of the distance from the source of light. 486. A Photometer is an instrument for comparing the intensity of... | |
 | William Watson - Physics - 1899 - 990 pages
...angles to the incident light, the intensity of illumination on the surface of the sphere is E 7*' Thus the intensity of the illumination varies inversely as the square of the distance from the luminous source. This law is known as the inverse square law. Since light is propagated... | |
 | Henry Smith Carhart, Horatio Nelson Chute - Physics - 1901 - 464 pages
...the radius, it follows that the energy per unit of area must decrease at the same rate. Therefore, the intensity of the illumination varies inversely as the square of the distance from the source of light. 237. A Photometer is an instrument for comparing the intensity of... | |
 | William Norris Mumper - Physics - 1907 - 434 pages
...1 and 4, bear the same relation to each other as the squares of the distance (20) 2 (40) 2 , hence the intensity of the illumination varies inversely as the square of the distance from the source. Remembering that light waves are spherical and that the surface of a sphere... | |
 | George James Burch - Eye - 1912 - 172 pages
...illumination will be evenly distributed only over a limited area around the axis of the beam. The law that the intensity of the illumination varies inversely as the square of the distance from the source holds if from the point considered nothing is visible through the diaphragm... | |
 | John Charles Stone, James Franklin Millis - Arithmetic - 1917 - 352 pages
...illumination, or intensity of light thrown upon a surface from a given source, depends upon the distance from the source. It is shown that : ' The intensity of...illumination varies inversely as the square of the distance from the source of light. Thus, a standard candle placed 2 ft. from an open book will illuminate... | |
 | Ernst Rudolph Breslich - Logarithms - 1917 - 408 pages
...the intensity of the illumination at the fourth corner is T6j- that at the center of the room. Given that the intensity of the illumination varies inversely as the square of the distance from the light. (Harvard.) CHAPTER II TRIGONOMETRIC FUNCTIONS 29. Angles in general. In the... | |
 | John Charles Duncan - Astronomy - 1926 - 474 pages
...greater, the greater the brightness of the star ; the relation being that which would be expected if the intensity of the illumination varies inversely as the square of the distance. The manner in which the stars cause the nebulae to shine is not known. VM Slipher, who discovered... | |
| |
The intensity of the illumination varies inversely as the square of the distance from the source of light. 