ok so my science teacher told me to find the answer this but i have no idea how...
ok so the problem goes
lusia conducted an experiment to determine the relationship between distance and the brightness of stars. She used a meterstick, a light meter, and a lightbulb. She placed the bulb at the zero end of the meterstick, then placed the light meter at the 20 cm mark and recorded the distance and the light- meter reading in her data table. readings are in luxes. luisa then measured the light intensity. luisa incread the distance from the bulb to the light meter and took more readings.
data [effects of distance on light]
distance(cm) meter reading (luxes)
20 4150.0
40 1037.5
60 461.1
80 259.4
10 ?????
what would be the light intensity for 10 cm???
2007-09-26 15:23:12 · 2 answers · asked by hmmm... 3 in Science & Mathematics ➔ Mathematics
get a piece of paper and draw the graph..
2007-09-26 15:26:59 · answer #1 · answered by Anonymous · 0⤊ 0⤋
We expect the light intensity to fall off as 1/r^2, where r is the distance. So if we multiply the intensity by the square of the distance we should get an approximately constant value.
distance(m) intensity (lux) dist^2 * intensity
0.20 4150.0 166
0.40 1037.5 166
0.60 461.1 166
0.80 259.4 166
So our expectation is confirmed. For a distance of 10 cm = 0.10 m, we therefore expect an intensity of 166/(0.1)^2 = 16600 luxes.
2007-09-26 22:29:57 · answer #2 · answered by Scarlet Manuka 7 · 1⤊ 0⤋