[kiaora]

hey

AQA A Biology: how do you convert µm to mm? this is specifically for questions which require you to work out the scale of drawings and magnifications.

thanks.xx

[corkskrew]

µm are x10^-6m
mm are x10^-4m

So there are 100µm in 1mm. Therefore divide by 100 to go from µm to mm

[Golden Maverick]

(Original post by corkskrew)
µm are x10^-6m
mm are x10^-4m

So there are 100µm in 1mm. Therefore divide by 100 to go from µm to mm

mm are x10^-3m

Making 1000µm in a mm.

[oxymoron]

(Original post by corkskrew)
µm are x10^-6m
mm are x10^-4m

So there are 100µm in 1mm. Therefore divide by 100 to go from µm to mm

No ... 10^-3 mm in a metre .... so divide by 1000 not 100

[Talya]

lol

You know, the conversions from mm, µm, etc are actually harder in biology than physics! I kid you not.

Stupid, eh?

-Kavanne

[OldakQuill]

Just remember - mille- means thousandth (like French).

Oldak.

[DaveManUK]

1e-6 -->> 1e-3
multiply by 1000 not divide

[Golden Maverick]

(Original post by DaveManUK)
1e-6 -->> 1e-3
multiply by 1000 not divide

No,
If I'm converting 100µm --> mm
you divide by 1000, to give 0.1mm

[DaveManUK]

i find it easier to work in standard form, same difference.

[theunforgiven]

hey then wht bout nm? coz there was this question in nm :
find the magnification where the length of drawing is 4mm and the length of the specimen object is 1nm?

[snmichaels]

mm = 1.0 x 10^-3m
um = 1.0 x 10^-6m
nm = 1.0 x 10^-9m

[corkskrew]

(Original post by corkskrew)
µm are x10^-6m
mm are x10^-4m

So there are 100µm in 1mm. Therefore divide by 100 to go from µm to mm

Apologies all. Friends 18th last night. Heavy head this morning. Won't happen again. Promise.

[oxymoron]

(Original post by corkskrew)
Apologies all. Friends 18th last night. Heavy head this morning. Won't happen again. Promise.

Lol - everyone makes mistakes - don't worry about it. As long as you don't go out to a friend's 18th the night before an exam that is!

[wacko_demon]

ok guys just to clear things up a bit....

how many nm would be in 4.2 mm
and
how many nm would be in 2.3um

thanks in advance

wacko_demon

[oxymoron]

(Original post by wacko_demon)
ok guys just to clear things up a bit....

how many nm would be in 4.2 mm
and
how many nm would be in 2.3um

thanks in advance

wacko_demon

4.2 mm = 4 200 000 nm

2.3 um = 2300 nm

[wacko_demon]

can u please include working out ???

wacko_demon

[snmichaels]

how many nm would be in 4.2 mm =
4.2 x 10⁶nm

and

how many nm would be in 2.3um =
2.3 x 10³nm

You'r welcome

[oxymoron]

(Original post by wacko_demon)
can u please include working out ???

wacko_demon

Right

units go: (biggest to smallest)

metres
mm
um
nm

to move up by one of those units (ie move up the list), you divide by 1000 because the unit becomes bigger so you have less of them
To move down the list, multiply by 1000 (smaller units - more of them)

so 4.2 mm --> nm
moving down by 2 units so multiply by 1000 twice

gives you 4200 x 1000 = 4 200 000

similarly 2.3 um ---> nm
moving down by 1 unit so multiply by 1000

gives you 2300 nm

[wacko_demon]

THANKS ALOT GUYS

wacko_DEMON

[snmichaels]

Y m to Y mm = Y m x 1000 mm

Y mm to Y um = Y mm x 1000 um

Y mm to Y nm = Y mm x (1000 x 1000) nm

Y nm to Y um = Ynm / 1000 um

etc...