Question

Two narrow slits are 0.4mm apart. The dark fringe of order 3 is 0.5 degrees from the central bright fringe. What is the wavelength of the light?

Answer 1

http://ocw.mit.edu/courses/physics/8-02sc-physics-ii-electricity-and-magnetism-fall-2010/interference/MIT8_02SC_notes31to32.pdf

Answer 2

let use this as a guide

Answer 3

alright let me take a look.

Answer 4

ok so for sure d=0.4mm lol we got something :P

Answer 5

\[m* \lambda= d sin(\theta)\]

let's plug in what we know

m=3

d=.4mm

theta=.5 degree


\[3 \lambda=.4/1000 sin(.5)\]

find \[\lambda\]

Answer 6

thats what i did!

Answer 7

but small question, why is it divided by 1000?

Answer 8

it is in millimeter, we want it in standard unit, meter

Answer 9

is it always in m? because the question wants it in nm so its after that we convert?

Answer 10

yes, all formulas tend to use standard units

Answer 11

damn, i thought you could use nm cuz for another i used that. ok that was stupid of me. let me submit my answer and we'll c if it is right. i really owe u tho man. thx :) what was ur answer?

Answer 12

let see if it is correct

Answer 13

0.015279m? = 15 279 068.26nm?

Answer 14

http://www.google.com/#hl=en&sclient=psy-ab&q=0.01527+meter+in+nm&oq=0.01527+meter+in+nm&aq=f&aqi=&aql=1&gs_sm=3&gs_upl=673l4811l0l5002l15l15l0l0l0l1l317l2552l3.8.3.1l15l0&gs_l=hp.3...673l4811l0l5002l15l15l0l0l0l1l317l2552l3j8j3j1l15l0.efis.1.&pbx=1&bav=on.2,or.r_gc.r_pw.r_qf.,cf.osb&fp=f3dffc7186102169&biw=1366&bih=667

Answer 15

its wrong, but i i realised out error, its 3.5 not 3 because its a dark slit whioch is a minimum! :D THANKS A LOT MAN 4 attempts isnt pretty but at least we got the job done :D

Answer 16

np

Answer 17

wanna do another 1 :P?

Answer 18

sure, but I am not really good in optics

Answer 19

http://openstudy.com/study#/updates/4f6541fae4b079c5c6329551
heres the question, sry im having major lag it is not posting my responses lol