52. • Structure of a virus. To investigate the structure ofBIO extremely small objects, such as viruses, the wavelength of theprobing wave should be about one-tenth the size of the objectfor sharp images. But as the wavelength gets shorter, theenergy of a photon of light gets greater and could damage ordestroy the object being studied. One alternative is to use elec-tron matter waves instead of light. Viruses vary considerably insize, but 50 nm is not unusual. Suppose you want to study sucha virus, using a wave of wavelength 5.00 nm. (a) If you uselight of this wavelength, what would be the energy (in eV) of asingle photon? (b) If you use an electron of this wavelength,what would be its kinetic energy (in eV)? Is it now clear whymatter waves (such as in the electron microscope) are oftenpreferable to electromagnetic waves for studying microscopicobjects?

a) The photon’s energy can be represented as, Here, h, c, λ, and ν represent Plank’s constant,…

a virus, using a wave of wavelength 5.00 nm. (a) If you use light of this wavelength, what would be the energy (in eV) of a single photon? (b) If you use an electron of this wavelength, what would be its kinetic energy (in ev)? Is it now clear why matter waves (such as in the electron microscope) are often preferable to electromagnetic waves for studying microscopic objects?

a virus, using a wave of wavelength 5.00 nm. (a) If you use light of this wavelength, what would be the energy (in eV) of a single photon? (b) If you use an electron of this wavelength, what would be its kinetic energy (in ev)? Is it now clear why matter waves (such as in the electron microscope) are often preferable to electromagnetic waves for studying microscopic objects?

Modern Physics

3rd Edition

ISBN:9781111794378

Author:Raymond A. Serway, Clement J. Moses, Curt A. Moyer

Publisher:Raymond A. Serway, Clement J. Moses, Curt A. Moyer

Chapter2: Relativity Ii

Section: Chapter Questions

Problem 32P

See similar textbooks

Similar questions

Integrated Concepts What double-slit separation would produce a first-order maximum at 3.00° for 25.0-keV x rays? The small answer indicates that the wave character of x rays is best determined by having them interact with very small objects such as atoms and molecules.
Integrated Concepts (a) Calculate the velocity of electrons that form the same pattern as 450-nm light when passed through a double slit. (b) Calculate the kinetic energy of each and compare them. (c) Would either be easier to generate than the other? Explain.
Integrated Concepts A certain heat lamp emits 200 W of mostly IR radiation averaging 1500 nm in wavelength. (a) What is the average photon energy in joules? (b) How many of these photons are required to increase the temperature of a person's shoulder by 2.0°C, assuming the affected mass is 4.0 kg with a specific heat of 0.83kcal/kgC. Also assume no other significant heat transfer. (c) How long does this take?
How can you tell that a hologram is a true three-dimensional image and that those in 3-D movies are not?
When is it necessary to use relativistic quantum mechanics?
Integrated Concepts On its high power setting, a microwave oven produces 900 W of 2560 MHz microwaves. (a) How many photons per second is this? (b) How many photons are required to increase the temperature of a 0.500-kg mass of pasta by 45.0°C assuming a specific heat of 0.900kcal/kgC ? Neglect all other heat transfer. (c) How long must the microwave operator wait for their pasta to be ready?
Construct Your Own Problem Consider the Doppler-shifted hydrogen spectrum received from a rapidly receding galaxy. Construct a problem in which you calculate the energies of selected spectral lines in the Balmer series and examine whether they can be described with a formula like that in the equation 1=R(1nf21ni2), but with a different constant R.
Integrated Concepts Sunlight above the Earth's atmosphere has an intensity of 1.30kW/m2. If this is reflected straight back from a mirror that has only a small recoil, the light's momentum is exactly reversed, giving the mirror twice the incident momentum. (a) Calculate the force per square meter of mirror. (b) Very low mass mirrors can be constructed in the near weightlessness of space, and attached to a spaceship to sail it. Once done, the average mass per square meter of the spaceship is 0.100 kg. Find the acceleration of the spaceship if all other forces are balanced. (c) How fast is it moving 24 hours later?
What is the velocity of a 0.400-kg billiard ball if its wavelength is 7.50 cm (large enough for it to interfere with other billiard balls)?
3) The “Photoelectric Effect” occurs whena)......................... is absorbed at a metal surface.The energy is transferred to an b).............................which may then be c)............................. from thesurface. Experiments with this effect wereproducing results that could not be explained.In 1905, Einstein used Plank’s e)...............................Theory to explain all the difficulties. His idea was:• Light is a wave, but the energy is concentrated in“bundles” called “f)................................”• Each bundle carries an amount of energy, asdescribed by g)....................................... theory.• When a photon interacts with matter, it can eithertransfer h).......................... of its energy, ori).............................. of it, but cannot transferj).....................................................
Integrated Concepts A carbon dioxide laser used in surgery emits infrared radiation with a wavelength of 10.6 m. In 1.00 ms, this laser raised the temperature of 1.00 cm3 of flesh to 100°C and evaporated it. (a) How many photons were required? You may assume flesh has the same heat of vaporization as water. (b) What was the minimum power output during the flash?
Which aspects of the photoelectric effect cannot be explained without photons? Which can be explained without photons? Are the latter inconsistent with the existence of photons?