Answer :
Final answer:
The intensity of light at 7 meters from the lamp fixture by using the inverse square law is 12.76 millilumens per second; none of the provided answer choices match this calculation.
Explanation:
The intensity of light from a lamp fixture is 625 millilumens per second at a distance of 1 meter. To find the intensity at a distance of 7 meters, we need to apply the inverse square law for light, which states that the intensity of light is inversely proportional to the square of the distance from the source. Mathematically, this can be expressed as I = I0/(d2), where I is the intensity at distance d, and I0 is the initial intensity at a distance of 1 meter.
Using this formula, the intensity at 7 meters would be:
625 millilumens / (72) = 625 millilumens / 49 = 12.76 millilumens per second
However, this answer does not match any of the options given in the question, suggesting there might be a typo in the question's answer choices.