# Physics

posted by J

Coherent light of frequency 6.32 * 10^14 Hz passes through two thin slits and falls on a screen 85 cm away. You observe that the third bright fringe occurs at +- (plus or minus) 3.11 cm on either side of the central bright fringe. (a) How far apart are the two slits? (b) At what distance from the central bright fringe will the third dark fringe occur?

once again, I am confused!

1. bobpursley

calculate lambda.

n*Lambda/s=w/d for the bright fringes.

N*lambda/2=w/d for the dark fringes. Now be careful on this one.

http://www.matter.org.uk/schools/Content/Interference/formula.html

## Similar Questions

1. ### Physics

Light of wavelength 680 nm falls on two slits and produces an interference pattern in which the fourth-order fringe is 47 mm from the central fringe on a screen 1.1 m away. What is the separation of the two slits?
2. ### physics

Monochromatic light with a wavelength of 5.0 E -7 meter passes through two narrow slits, producing an interference pattern on a screen 3.0 meters away. The first order bright band lines 2.0 E -2 meters away from the central bright …
3. ### Physics

Two slits are 0.144 mm apart. A mixture of red light (wavelength = 665 nm) and yellow-green light (wavelength = 565 nm) falls on the slits. A flat observation screen is located 2.11 m away. What is the distance on the screen between …
4. ### Physics (PLEASE HELP)

Two slits are 0.144 mm apart. A mixture of red light (wavelength = 665 nm) and yellow-green light (wavelength = 565 nm) falls on the slits. A flat observation screen is located 2.11 m away. What is the distance on the screen between …
5. ### Physics

In an interference of light experiment, coherent light that contains two wavelengths: 640 nm (red-orange) and 425 nm (indigo-blue), passes through two narrow slits separated by 5.35 Î¼m, and the interference pattern is observed on …
6. ### Physics

In an interference of light experiment, coherent light that contains two wavelengths: 614 nm (red-orange) and 429 nm (indigo-blue), passes through two narrow slits separated by 3.12 μm, and the interference pattern is observed …
7. ### Physics

In an interference of light experiment, coherent light that contains two wavelengths: 640 nm (red-orange) and 425 nm (indigo-blue), passes through two narrow slits separated by 5.35 Î¼m, and the interference pattern is observed on …
8. ### physics

Coherent light of frequency 6.38×1014 Hz passes through two thin slits and falls on a screen 80.0 cm away. You observe that the third bright fringe occurs at ± 3.08 cm on either side of the central bright fringe. How far apart are …
9. ### physics

Coherent light of frequency 6.30 1014 Hz passes through two thin slits and falls on a screen 75.0 cm away. You observe that the third bright fringe occurs at ±3.06 cm on either side of the central bright fringe. (a) How far apart …
10. ### physics

Two slits are 0.158 mm apart. A mixture of red light ( wavelength = 65 nm) and yellow green light (wavelength = 565 nm)falls on the slits. A flat observation screen is located 2.24 m away. What's the distance on the screen between …

More Similar Questions