...volume is equivalent to two cones with altitudes 5 and 11 and radii 2 and 4 respectively. 16. Assume that the illumination from a source of light varies inversely as the square of the distance. A book is now held 18 in. from a lamp. How much farther away must it be moved in order to...

...the earth is 4000 miles, at what distance from the earth would a body weigh only half as much? 17. The illumination from a source of light varies inversely as the square of the distance from the source. How far must a photographic plate, that is 12 inches from a lamp, be moved...

...volume equals that of the sum of two spheres whose radii are respectively 6 feet and 3.5 feet. 19. The illumination from a source of light varies inversely as the square of the distance. How far must a screen that is 10 feet from a lantern be moved in order to receive one fourth...

...inches, is 32f square inches, what will be the edge of a cube whose surface is 30| square inches? 19. The illumination from a source of light varies inversely as the square of the distance from the light. If a book, now 10 inches away from the light, is moved to 20 inches distance,...

...is inversely proportional to the cube of x. EXAMPLE The study of physics shows that the intensity of illumination / from a source of light varies inversely as the square of the distance d from the source. In other words, there is a constant k such that JOINT VARIATION The terminology...