Physics - Please Help!
posted by Alex .
I really need help on these questions because I have a test tomorrow and don't understand how to do them.
1) A wire of diameter 0.6mm is placed in the path of light coming from a laser. Light diffracts around both sides of the wire; the diffracted waves then interfere with one another, thus producing an interference pattern of the double slit type on a screen located 9m from the wire. The wavelength is 640nm.
a) How far apart are the nodal lines observed on the screen?
b) How many nodal lines should be observed in the 50cm wide screen?
c) Suppose that a wire of larger diameter were used. What changes should be observed in the interference pattern?
Use the same equation as you would use for single-slit diffraction. Go to
if you need to review the subject.
If the wire diameter is increased, the spacing of the "nodal lines" (zeros) decreases in inverse proportion to the wire width.