# Magnification Question Watch

Question 1aiii)

Actual Size = Image Size/Magnification

Image Size = 15mm x 1000 (to conver to micrometers) = 15000

Mark scheme says divide by 4000, but why because it doesnt say magnification is 4000 :/

Thanks!
2. You have to calculate the magnification using the scale.
3. The scale is 20 um which is 20micrometers - how would i do that?
4. The magnification is what the scale line thing represents, divided by how long it actually is (in mm converted to micrometres), then put that in the formula

EDIT: or maybe its the other way round as in how long it actually is, divided by what length it represents I'm gonna get my practice paper out, i'll tell you in a sec
5. So if the whole cell is 75mm x 1000 = 75000 micrometers then divide that by 20 which is 3750 micrometers - which is the magnifcation? P:
6. okay, magnification is the length of the scale bar thing, divided by the length it represents
7. There's a link at the top of the post
The scale is 20 um which is 20micrometers - how would i do that?
Is that what it represents? You have to measure the scale line with a ruler and see how long it is, convert that to um, then divide that by 20um. Are you doing OCR Jan 09 by any chance?
9. Yep, done that - i think i got the right answer now.

And yep
10. I got my teacher to help me with that question
he did some of it for me:

the scale line is 80mm and that represents 20 micrometres
magnification = image size divided by actual size, so thats 80,000 micrometres (converting 80mm to um), divided by 20 micrometres, which is 4000 micrometres. hope that helps
Yep, done that - i think i got the right answer now.

And yep
WOOOOOOOOO, congrats.
This reminds me... I need to do some biology revision good luck with your exams!

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Updated: December 27, 2010
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