Answer:
0.01125 foot-candles
Step-by-step explanation:
According to the data, intensity of light measured in foot-candles varies inversely with the square of the distance from the light source
Therefore,
[tex]I[/tex] α 1/[tex]d^{2}[/tex]
[tex]I[/tex] = k/ [tex]d^{2}[/tex]
where,
'k' is the constant
'd' is the distance from bulb
'[tex]I[/tex] ' is intensity of a light bulb
When,
d= 3meters
[tex]I[/tex] = 0.08foot-candles
k= [tex]I[/tex] . [tex]d^{2}[/tex]
k= 0.08 x 3² => 0.08 x 9
k= 0.72
Next is to determine the intensity level at 8 meters.
[tex]I[/tex] = k/ [tex]d^{2}[/tex]
[tex]I[/tex] = 0.72/ 8²
[tex]I[/tex] = 0.01125 foot-candles
Therefore, the intensity level at 8 meters is 0.01125 foot-candles
The intensity of light measured in foot-candles varies inversely with the square of the distance from the light source. The intensity level at 8 meters is 0.01125 foot-candles
A partial variation shows the relation between two variables whereby the dependent variable refers to the sum of a particular constant number and a constant.
From the information given;
So I varies inversely to the d².
i.e.
[tex]\mathbf{I \ \alpha \dfrac{k}{d^2}}[/tex]
By cross multiply;
[tex]\mathbf{k = Id^2}[/tex]
when;
∴
Using the same formula:
[tex]\mathbf{I = \dfrac{0.72 foot-candles . \ meters}{64 \ meters}}[/tex]
I = 0.01125 foot-candles
Therefore, the intensity level at 8 meters is 0.01125 foot-candles.
Learn more about partial variation here:
https://brainly.com/question/18284421?referrer=searchResults
