Answer:
[tex]157.5W/m^2[/tex]
Explanation:
We are given that
[tex]I=70w/m^2[/tex]
When d=3 m
We have to find the intensity when the distance from the light bulb is 2 m away.
According to question
Intensity,[tex]I\propto\frac{1}{d^2}[/tex]
[tex]I=\frac{kd^2}[/tex]
Where k=Proportionality constant.
Substitute the values
[tex]70=\frac{k}{3^2}[/tex]
[tex]k=70\times 3^2=630[/tex]
Intensity when d=2 m
[tex]I=\frac{630}{2^2}=157.5W/m^2[/tex]
