http://www.ck12.org Chapter 15. Diffraction and Interference of Light
(d) constructive interference.- In a double slit experiment with slits 1. 00 × 10 −^5 mapart, light casts the first bright band 3. 00 × 10 −^2 mfrom
the central bright spot. If the screen is 0.650 m away, what is the wavelength of this light?
(a) 510 nm
(b) 390 nm
(c) 430 nm
(d) 460 nm - Violet light falls on two slits separated by 1. 90 × 10 −^5 m. A first order bright line appears 13.2 mm from the
central bright spot on a screen 0.600 m from the slits. What is the wavelength of the violet light? - Suppose in the previous problem, the light was changed to yellow light with a wavelength of 5. 96 × 10 −^7 mwhile
the slit separation and distance from screen to slits remained the same. What would be the distance from the
central bright spot to the first order line? - Light with a wavelength of 6. 33 × 10 −^7 mis used in a double slit experiment. The screen is placed 1.00 m
from the slits and the first order line is found 65.5 mm from the central bright spot. What is the separation
between the slits?
- diffraction:Change in the directions and intensities of a group of waves after passing by an obstacle or
through an aperture whose size is approximately the same as the wavelength of the waves. - monochromatic:Light having only one wavelength.
- constructive interference:The interference of two or more waves of equal frequency and phase, resulting
in their mutual reinforcement and producing a single amplitude equal to the sum of the amplitudes of the
individual waves. - destructive interference:The interference of two waves of equal frequency and opposite phase, resulting in
their cancellation where the negative displacement of one always coincides with the positive displacement of
the other.