Question 1: To help you think about how illuminance varies with distance, suppose a small light source is placed at the center of two transparent spheres. One sphere has a radius,R, and the other a radius,2R. L lumens of light leave the light source and travel outward toward the spheres. How does the illuminance (the lumens passing through each square meter of surface) at the inner sphere compare to the illuminance at the outer sphere,assuming no light absorption? Try to solve this problem by thinking about the following:

1) how much of the light passes through the first sphere? how much passes through the second sphere?

2)how do the surface areas of the two spheres compare?

Question 2: Since most light bulbs that you use are not true point sources of light, how do you think the answer to question 1 would change if a typical light bulb were used?