Then why does the new silicon kilogram prototype need to be made out of pure isotope silicon-28?
Does the lattice constant of a unit cell vary over isotopes? e.g Si 28 and Si 29
what do the phrases "Je veux me battre" and "voulu mettre ton destin à genou" (there not related).?
Do you know any good, free audio dictionary-type websites that speack chinese?
Then, in the light intensity equation E=L/r^2, where E is illumination, L is luminous intensity and r is distance, what are the units of each factor?
Does one Candela (SI Unit for lumious intesnity) = lumens per metre squared, i.e. 1 Cd = 1 lum/m^2 if not, what is the relationship between candela and lumens?
HOw would I say "Dear son" and "Love from" in German?
do converging/diverging lenses work because of refraction?
When would one use the term ressentir as opposed to sentir?
I am doing a project on Isaac Newton. Ive looked at his impact on the development of the telescope, in particular, the reflecting telescope. Ive researed this a bit and have found conflicting dates. Some sources say he built the first relflecting telescope in 1671 but others g...