Exam 34: Wave and Particle Optics

Light of wavelength 687 nm is incident on a single slit 0.75 mm wide. At what distance from the slit should a screen be placed if the second dark fringe in the diffraction pattern is to be 1.7 mm from the center of the diffraction pattern?

A metal having a work function of 2.5 eV is illuminated with white light that has a continuous wavelength band from 400 nm to 700 nm.For which one of the following ranges of the wavelength band in this white light are photoelectrons NOT produced? (h = 6.626 × 10^-34 J • s,c = 3.00 × 10⁸ m/s, 1 eV = 1.60 × 10^-19 J)

Light of wavelength 500 nm illuminates a round 0.50-mm diameter hole.A screen is placed 6.3 m behind the slit.What is the diameter of the central bright area on the screen?

A metallic sheet has a large number of slits,5.0 mm wide and 20 cm apart,and is used as a diffraction grating for microwaves.A wide parallel beam of microwaves is incident normally on the sheet.If the microwave wavelength is 6.0 cm,what is the largest angle away from the central maximum at which an intensity maximum occurs.

A nonrelativistic electron is accelerated from rest through a potential difference.After acceleration the electron has a de Broglie wavelength of 880 nm.What is the potential difference through which this electron was accelerated? (h = 6.626 × 10^-34 J • s,e = 1.60 × 10^-19 C,m_el = 9.11 × 10^-31 kg)

In a double slit experiment,the slit separation is constructed to be exactly 4 times the wavelength of the light passing through the slits. At what angles from the center of the pattern will the third bright fringes on both sides of the central fringe occur?

Gamma rays are photons with very high energy. How many visible-light photons with a wavelength of 500 nm would you need to match the energy of a gamma-ray photon with energy 4.1 × 10^-13? (h = 6.626 × 10^-34 J • s,c = 3.00 × 10⁸ m/s)

When a metal surface is illuminated with light of wavelength 437 nm,the stopping potential for photoelectrons is 1.67 V.(c = 3.00 × 10⁸ m/s,h = 6.626 × 10^-34 J • s,e = - 1.60 × 10^-19 C,1 eV = 1.60 × 10^-19 J,m_el = 9.11 × 10^-31 kg) (a)What is the work function of the metal,in eV? (b)What is the maximum speed of the ejected electrons?

A stopping potential of 0.50 V is required when a phototube is illuminated with monochromatic light of wavelength 590 nm.Monochromatic light of a different wavelength is now shown on the tube,and the stopping potential is measured to be 2.30 V.What is the wavelength of this new light? (c = 3.00 × 10⁸ m/s,e = - 1.60 × 10^-19 C,h = 6.626 × 10^-34 J • s,1 eV = 1.60 × 10^-19 J)

An 84-kW AM radio station broadcasts at 1000 kHz .How many photons are emitted each second by the transmitting antenna? (h = 6.626 × 10^-34 J • s)

White light is incident normally on a thin soap film having an index of refraction of 1.34.It reflects with an interference maximum at 684 nm and an interference minimum at 570 nm with no minima between those two values.The film has air on both sides of it.What is the thickness of the soap film?

Monochromatic light strikes a metal surface and electrons are ejected from the metal.If the intensity of the light is increased,what will happen to the ejection rate and maximum energy of the electrons?

A thin beam of laser light of wavelength 514 nm passes through a diffraction grating having 3952 lines/cm.The resulting pattern is viewed on a distant curved screen that can show all bright fringes up to and including ±90.0° from the central spot.If the experiment were performed with all of the apparatus under water (which has an index of refraction of 1.33),what would be the TOTAL number of bright spots that would show up on the screen?

In a two-slit experiment,the slit separation is 3.00 × 10^-5 m.The interference pattern is recorded on a flat screen-like detector that is 2.00 m away from the slits.If the seventh bright fringe on the detector is 10.0 cm away from the central fringe,what is the wavelength of the light passing through the slits?

Light from a monochromatic source shines through a double slit onto a screen 5.00 m away.The slits are 0.180 mm apart.The dark bands on the screen are measured to be 1.70 cm apart.What is the wavelength of the incident light?

A piece of glass has a thin film of gasoline floating on it.A beam of light is shining perpendicular on the film.If the wavelength of light incident on the film is 560 nm and the indices of refraction of gasoline and glass are 1.40 and 1.50,respectively,what is the minimum nonzero thickness of the film to see a bright reflection?

Light of wavelength 425.0 nm in air falls at normal incidence on an oil film that is 850.0 nm thick.The oil is floating on a water layer 15 cm thick.The refractive index of water is 1.33,and that of the oil is 1.40.You want to add oil so that light reflected off of the top of the oil film will be canceled.What is the minimum distance that you should INCREASE the oil film?

A researcher is investigating a cubic crystal with x-rays.He is looking at Bragg reflection from the planes parallel to the cube faces.He finds that when using x-rays of 0.165 nm a strong first maximum occurs when the beam makes an angle of 23.5° with the planes.What is the spacing of adjacent atoms in the crystal?

Light of wavelength 400 nm falls on a metal surface having a work function 1.70 eV.What is the maximum kinetic energy of the photoelectrons emitted from the metal? (c = 3.00 × 10⁸ m/s, H = 6.626 × 10^-34 J • s = 4.141 × 10^-15 ev • s,1 eV = 1.60 × 10^-19 J)

A metal having a work function of 2.4 eV is illuminated with monochromatic light whose photon energy is 4.0 eV.What is the maximum kinetic energy of the photoelectrons produced by this light? (h = 6.626 × 10^-34 J • s,1 eV = 1.60 × 10^-19 J)