Question

Light of wavelength 270 nm strikes a metal whose work function is 1.9 eV. What is...

Light of wavelength 270 nm strikes a metal whose work function is 1.9 eV. What is the shortest de Broglie wavelength for the electrons that are produced as photoelectrons?

Homework Answers

Answer #1

First find the energy "E" of the incoming light (photons) from;

E = hc/D , (D is the given wavelength in meters, h is Planck's constant in Joules-sec)

= (6.63*10^-34)(3*10^8)/(270*10^-9)

= 7.37*10^-19 J

The maximum kinetic energy of the emitted photoelectrons is the difference between the photon energy and the given work function;

KE = E - W = (7.37*10^-19) – (1.9*1.602*10^-19) = 4.32*10^-19 J

The maximum momentum of the photoelectrons is then;

P = SqRt(2m*KE), m is the electron mass.

= 8.87*10^-25 kg-m/s

Finally, the minimum DE Broglie wavelength "L" is;

L = h/P

= 7.47 x 10-10 m

Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
Light of wavelength 300 nm strikes a metal whose work function is 2.0 eV. What is...
Light of wavelength 300 nm strikes a metal whose work function is 2.0 eV. What is the shortest de Broglie wavelength for the electrons that are produced as photoelectrons? Express your answer using two significant figures. λmin=    m
Consider electrons at the surface of a metal whose work function is 2.4 eV. Laser light...
Consider electrons at the surface of a metal whose work function is 2.4 eV. Laser light of wavelength 350 nm and power output of 100 mW is shone on this metal, and all the energy of each photon is absorbed by the electrons at the surface. If we model the de Broglie wave function of the electrons as plane waves, how many electrons per second do we expect to see ejected from the metal’s surface? (5) Hint: treat the work...
A certain metal has a work function of 2.6 eV. (a) What is the shortest wavelength...
A certain metal has a work function of 2.6 eV. (a) What is the shortest wavelength of the electromagnetic radiation that will eject electrons from this material? (b) If light of wavelength 420 nm is used, what will be the speed of the emitted electrons?
Light that has a 192 nm wavelength strikes a metal surface, and photoelectrons are produced moving...
Light that has a 192 nm wavelength strikes a metal surface, and photoelectrons are produced moving as fast as 0.002c. 1) What is the work function of the metal? (Express your answer to three significant figures.) ×10^−19J 2) What is the threshold wavelength for the metal above which no photoelectrons will be emitted? (Express your answer to three significant figures.) nm
Photoelectrons are observed when a metal surface is illuminated by light with a wavelength 437 nm....
Photoelectrons are observed when a metal surface is illuminated by light with a wavelength 437 nm. The stopping potential for the photoelectrons in this experiment is 1.67V. a. What is the work function of the metal, in eV? b. What type of metal is used in this experiment? c. What is the maximum speed of the ejected electrons?
1. Light of wavelength 401 nm incident on a certain metal produces photoelectrons with a maximum...
1. Light of wavelength 401 nm incident on a certain metal produces photoelectrons with a maximum kinetic energy of 1.78 eV. What is the maximum wavelength of light capable of producing photoelectrons for this metal? 2. Electrons in an electron microscope have been accelerated through a potential difference of 1250 V. How large is their de Brogile wavelength?
You illuminate a metal with light of wavelength 590 nm and find that the photoelectrons have...
You illuminate a metal with light of wavelength 590 nm and find that the photoelectrons have a maximum kinetic energy of 0.70 eV. You then illuminate the same metal with light of another wavelength and find a maximum kinetic energy of 1.9 eV for the photoelectrons. What is the second wavelength, in nanometers?
The work function of potassium metal is 2.30 eV. Monochromatic light is shined on its surface,...
The work function of potassium metal is 2.30 eV. Monochromatic light is shined on its surface, and photoelectrons with a maximum speed of 5.50E5 m/s are ejected. What is the wavelength of the light? 539 nm 657 nm 393 nm 157 nm 1443 nm
a) A photon of wavelength 43 nm is incident upon a metal in a photoelectric apparatus....
a) A photon of wavelength 43 nm is incident upon a metal in a photoelectric apparatus. A stopping voltage of 21 V was obtained. What is the threshold frequency of the metal? (format of a.b x 10cdHz) b) Light with a frequency of 5.00 x 1014 Hz illuminates a photoelectric surface that has a work function of 2.10 x 10-19 J. What is the maximum kinetic energy of the emitted photoelectrons? (format of a.bc x 10-de J ) c) Light...
Light of wavelength 235 nm is incident on Magnesium in a photoelectric effect experiment. The work...
Light of wavelength 235 nm is incident on Magnesium in a photoelectric effect experiment. The work function of Magnesium is 3.68 eV. (a) What is the maximum kinetic energy of the emitted electrons, in eV? (b)What is the maximum velocity of the emitted electrons, in m/s? (c) What is the stopping potential, in Volts, that results in no collected photoelectrons? (d) Light of wavelength 235 nm is now incident on lead (work function 5.40 eV). What is the maximum kinetic...