what is the mass in kilograms, of a piece of aluminium of volume 3.6x10^-5 m^3( Density 2700 kg m^-3)?
The really neat thing about physics is that the units in a question often nearly give you the answer! The units of density are kg [mass] / m^3 [volume] So right away that gives you the equation density mass / volume without you needing to remember itSo, multiply both sides of that equation by volume and you get: density volume mass [just like variables, volume cancels on the right hand side] Plug in your values: mass 2700 kg m^-3 3.6 10^-5 m^3 mass 0.0972 kg Since the values we are given are quoted to 2 significant figures, we should round our answer and give it to the same level of precision: mass 0.097 kg
It's really just personal preference, and the yarn you're using can be just as much factorSo if you're knitting with a particularly slubby yarn, I think the waxed would be helpfulBut if you're knitting with a slinky/slick yarn you might want something with more gripI don't think there's a one kind fits all answer since there are other factors.
Metal needles are slippery and for those of us who want to knit really fast, metal needles are the way to goPlastic needles are not quite so slipperyBamboo needles are NOT slippery at all and, therefore, are quite good for those who have trouble with stitches slipping off the tipsI HATE bamboo needles, but many people love themClover is a major maker of bamboo needlesI would say try ONE PAIR and see how you like them before you invest in lots of needles.
