# Find the angular width of the central maximum.

## Homework Statement

A single slit of width 1.50 * 10-6m is illuminated with light of wavelength 500.0 nm. Find the angular width of the central maximum.

θ = λ / b

## The Attempt at a Solution

b = 1.50 * 10-6m
λ = 5.000 * 10-7
θ = λ / b = 0.333 = 19.1°

All my calculation of diffraction on single slit is off-target. It seems there is a fundamental point that I am missing. Please help. Related Introductory Physics Homework Help News on Phys.org
You have found the angular position,measured from the centre,of the pattern.There are two such minima,one on each side of the central maxima.

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OK.. so what I need is 2Θ, right? Then I got 38.2, and this is a bit off from 38.9. Where did this difference come from?

I calculated it to be 38.9.The equation is:
sin theta=lambda/d.
Did you take theta to be in radians?If so that is a good approximation but only for very small angles.

Now I can solve the problems. Thanks everyone!! :D

p.s. Emily, the link is not valid. Could you give me a right one? I can solve the problems, but still I want to check it out.