You asked your roommate Joe to buy some replacement light bulbs for fixtures around the house

since some of them went out recently in three locations (outside your front door, above your

stove top and the lamp in your reading nook). He comes back with several packages of 40 W light

bulbs. You thank him but also let him know that you assumed that he would get different wattages

for the different placements of bulbs around the house. Joe states that wattages on the packages

"don't really matter than much" and "everything is pretty much the same if you're close enough

to the light source".

a. Is there any validity to what Joe is saying? In what ways are Joe's statements correct or

incorrect?

You can tell that Joe isn't going to return the 40 W bulbs. You choose to try to work with them,

installing them in the three previously mentioned locations around the house. You notice the difference in lighting from what is was previously immediately. The most distinct difference is the outside light near the front door. Previously, there was a 100 W light bulb in the light fixture.

b. Assuming that both light bulbs have the same efficiency for converting electrical energy

in the circuit into emitted electromagnetic energy, at what distance (in m) does a 40 W

light bulb produce the same intensity of light that a 100 W light bulbs produces 15

m away?

You decided to replace all of the 40 W bulbs that you just installed with 100 W light bulbs, but this seems to be an overcorrection for your reading nook.

c. Assuming that both light bulbs have the same efficiency for converting electrical energy

in the circuit into emitted electromagnetic energy, how many times brighter would the

light from a 100 W light bulb be than a 40 W light bulb when both are observed 1.5 meters

away from the source?

The suggested light bulb wattage for a range hood is between 25-50 Watts.

d. Considering the previous two calculations as well, make a brief summary statement

that addresses power, light intensity and distance.