I'm trying to get into Biology, reading introductory texts. A discussion on E.Coli estimates the mass of the cell from $$density =1g/mL=1g/cm^3$$ and $$volume=1µm^3$$ From this I get $$ mass=density × volume = \frac {10^{-6} g}{10^{-2}}=10^{-4} g$$ which is wrong since the answer is supposed to be $1pg$. What am I doing wrong? Thanks!
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Its simple:
Mass = Density * Volume
= 10^3 (Kg/m3) * (10^-18 m3)
= 10^-15 Kg
which is equal to 10^-12 gram or 1pico gram
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$\begingroup$ Wiki gives me micrometers to be $10^{-6}m$. And also that an $mL=cm^3$. Since I don't come from a background where units were ever used, can u please elaborate on how u got ur density and volume compared to mine? Thanks $\endgroup$ – Mike Jun 7 '16 at 1:16
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$\begingroup$ @Craig Yes micrometers are indeed
10^-6meters. But1 micrometer^3=(10^-6)^3=10^-18$\endgroup$ – Failed Scientist Jun 7 '16 at 2:42 -
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2$\begingroup$ Ahh... I should've paid attention in high school physics $\endgroup$ – Mike Jun 7 '16 at 3:44
