A sodium vapor lamp (λ ~ 6 ´ 10-7 m) radiates 100 w of output uniformly in all directions. At what distance from the lamp will the photons have an average density of 106 m-3 ?.

What is meant by the statement" the melting poin of glycerine is 13 degree celsius

Gather reliable information to brent make his decision. to gather this information, use newspapers, call insurance companies or look at their web sites, and review consumer magazines and web sites. also, look at the manufacturer web site or for information about gas mileage. list the sources you use and take notes.

What is the role of lenses in microscopy?