The work function of Lithium is 2.3 eV. What is the cutoff frequency for Lithium? a) 1.8*10-15 Hz.                b) 5.55*1016 Hz.                       c) 5.55*1014 Hz.            d) none of these.

The energy-level diagram for the atomic emission spectra of an unknown gas is presented in the diagram below. n = 4 4.0 ev n = 3 1.8 eV n = 2 1.5 ev n=1 O ev Part A Initially, electrons are only in the ground state (n=1). A beam of red light hits the gas. This beam is a continuous spectrum of red light (from 620 nm to 750 nm) How many absorption line/s will there be in the spectra? 1 Correct Part B Initially, electrons are only in the ground state (n=1). A beam of red light hits the gas. This beam is a continuous spectrum of red light (from 620 nm to 750 nm) Calculate the wavelength of the absorption line ? da = nm Submit Previous Answers Request Answer X Incorrect; Try Again; 4 attempts remaining

A metal has a work function of 1.55 eV. Light with a frequency of 8.25x10^14 Hz is incident on the  metal. What is the stopping voltage?

If you are shining light on a Pt electrode and no electrons are emitted, what do you have to do to generate electrons? Decrease the wavelength of the light to increase the energy of the photons to emit electrons Electrons can not be emitted from Pt because like any other noble metal it does not react, even under light exposure (unlike other metals, e.g. Na, Sr or Cu) Increase the wavelength of the light to increase the energy of the photons to emit electrons Wait longer times or increase the intensity of the light source, since the energy of the absorbed light is not high enough to emit electrons from Pt surface

An electron is orbiting in the n = 3 orbit of an hydrogen atom. It is promoted by absorption of light energy to the n = 4 level. The Rydberg constant is R = 1.097 x 107 m-1. What is the wavelength of the light absorbed? Select one: a. 427 nm b. 1.094 μm c. 1.875 μm d. 763 nm

A laser with power output of 2.0 mW at a wavelength of 400 nm is projected onto a Calcium metal. The binding energy is 2.31 eV. i. How many electrons per second are ejected? ii. What power is carried away by the electrons?