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Problems&Exercises

Integrated Concepts

The 54.0-eV electron in [link] has a 0.167-nm wavelength. If such electrons are passed through a double slit and have their first maximum at an angle of 25 . size 12{"25" "." 0°} {} , what is the slit separation d size 12{d} {} ?

0.395 nm

Integrated Concepts

An electron microscope produces electrons with a 2.00-pm wavelength. If these are passed through a 1.00-nm single slit, at what angle will the first diffraction minimum be found?

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 . C size 12{2 "." 0°C} {} , assuming the affected mass is 4.0 kg with a specific heat of 0 .83 kcal /kg ºC size 12{0 "." "83"" kcal/kg" cdot °C} {} . Also assume no other significant heat transfer. (c) How long does this take?

(a) 1.3 × 10 19 J size 12{1 "." "33" times "10" rSup { size 8{ - "19"} } " J"} {}

(b) 2 . 1 × 10 23 size 12{2 "." 1 times "10" rSup { size 8{"23"} } } {}

(c) 1 . 4 × 10 2 s size 12{1 "." 4 times "10" rSup { size 8{2} } " s"} {}

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 . C size 12{"45" "." 0°C} {} , assuming a specific heat of 0 . 900 kcal/kg ºC size 12{0 "." "900"" kcal/kg" cdot °C} {} ? Neglect all other heat transfer. (c) How long must the microwave operator wait for their pasta to be ready?

Integrated Concepts

(a) Calculate the amount of microwave energy in joules needed to raise the temperature of 1.00 kg of soup from 20 . C size 12{"20" "." 0°C} {} to 100 ºC size 12{"100"°C} {} . (b) What is the total momentum of all the microwave photons it takes to do this? (c) Calculate the velocity of a 1.00-kg mass with the same momentum. (d) What is the kinetic energy of this mass?

(a) 3 . 35 × 10 5 J size 12{3 "." "35" times "10" rSup { size 8{5} } " J"} {}

(b) 1 . 12 × 10 –3 kg m/s size 12{1 "." "12" times "10" rSup { size 8{"–3"} } " kg" cdot "m/s"} {}

(c) 1 . 12 × 10 –3 m/s size 12{1 "." "12" times "10" rSup { size 8{"–3"} } " m/s"} {}

(d) 6.23 × 10 –7 J size 12{6 "." "23" times "10" rSup { size 8{"–7"} } " J"} {}

Integrated Concepts

(a) What is γ size 12{γ} {} for an electron emerging from the Stanford Linear Accelerator with a total energy of 50.0 GeV? (b) Find its momentum. (c) What is the electron’s wavelength?

Integrated Concepts

(a) What is γ size 12{γ} {} for a proton having an energy of 1.00 TeV, produced by the Fermilab accelerator? (b) Find its momentum. (c) What is the proton’s wavelength?

(a) 1 . 06 × 10 3 size 12{1 "." "07" times "10" rSup { size 8{3} } } {}

(b) 5 . 33 × 10 16 kg m/s size 12{5 "." "34" times "10" rSup { size 8{ - "16"} } `"kg" cdot "m/s"} {}

(c) 1 . 24 × 10 18 m size 12{1 "." "24" times "10" rSup { size 8{ - "18"} } `m} {}

Integrated Concepts

An electron microscope passes 1.00-pm-wavelength electrons through a circular aperture 2 . 00 μm size 12{2 "." "00 μm"} {} in diameter. What is the angle between two just-resolvable point sources for this microscope?

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.

(a) 1 . 62 × 10 3 m/s size 12{1 "." "62" times "10" rSup { size 8{3} } " m/s"} {}

(b) 4 . 42 × 10 19 J size 12{4 "." "41" times "10" rSup { size 8{ - "19"} } " J"} {} for photon, 1 . 19 × 10 24 J size 12{1 "." "19" times "10" rSup { size 8{ - "24"} } `J} {} for electron, photon energy is 3 . 71 × 10 5 size 12{3 "." "71" times "10" rSup { size 8{5} } } {} times greater

(c) The light is easier to make because 450-nm light is blue light and therefore easy to make. Creating electrons with 7.43 μeV size 12{7 "." "43"`"μeV"} {} of energy would not be difficult, but would require a vacuum.

Integrated Concepts

(a) What is the separation between double slits that produces a second-order minimum at 45 . size 12{"45" "." 0°} {} for 650-nm light? (b) What slit separation is needed to produce the same pattern for 1.00-keV protons.

(a) 2 . 30 × 10 6 m size 12{2 "." "30" times "10" rSup { size 8{ - 6} } " m"} {}

(b) 3 . 20 × 10 12 m size 12{3 "." "20" times "10" rSup { size 8{ - "12"} } `m} {}

Integrated Concepts

A laser with a power output of 2.00 mW at a wavelength of 400 nm is projected onto calcium metal. (a) How many electrons per second are ejected? (b) What power is carried away by the electrons, given that the binding energy is 2.71 eV? (c) Calculate the current of ejected electrons. (d) If the photoelectric material is electrically insulated and acts like a 2.00-pF capacitor, how long will current flow before the capacitor voltage stops it?

Integrated Concepts

One problem with x rays is that they are not sensed. Calculate the temperature increase of a researcher exposed in a few seconds to a nearly fatal accidental dose of x rays under the following conditions. The energy of the x-ray photons is 200 keV, and 4 . 00 × 10 13 size 12{4 "." "00" times "10" rSup { size 8{"13"} } } {} of them are absorbed per kilogram of tissue, the specific heat of which is 0 . 830 kcal/kg ºC size 12{0 "." "830"" kcal/kg" cdot °C} {} . (Note that medical diagnostic x-ray machines cannot produce an intensity this great.)

3 . 69 × 10 4 ºC size 12{3 "." "69" times "10" rSup { size 8{ - 4} } `°C} {}

Integrated Concepts

A 1.00-fm photon has a wavelength short enough to detect some information about nuclei. (a) What is the photon momentum? (b) What is its energy in joules and MeV? (c) What is the (relativistic) velocity of an electron with the same momentum? (d) Calculate the electron’s kinetic energy.

Integrated Concepts

The momentum of light is exactly reversed when reflected straight back from a mirror, assuming negligible recoil of the mirror. Thus the change in momentum is twice the photon momentum. Suppose light of intensity 1 . 00 kW/m 2 size 12{1 "." "00 kW/m" rSup { size 8{2} } } {} reflects from a mirror of area 2 . 00 m 2 size 12{2 "." "00 m" rSup { size 8{2} } } {} . (a) Calculate the energy reflected in 1.00 s. (b) What is the momentum imparted to the mirror? (c) Using the most general form of Newton’s second law, what is the force on the mirror? (d) Does the assumption of no mirror recoil seem reasonable?

(a) 2.00 kJ

(b) 1 . 33 × 10 5 kg m/s size 12{1 "." "33" times "10" rSup { size 8{ - 5} } `"kg" cdot "m/s"} {}

(c) 1 . 33 × 10 5 N size 12{1 "." "33" times "10" rSup { size 8{ - 5} } " N"} {}

(d) yes

Integrated Concepts

Sunlight above the Earth’s atmosphere has an intensity of 1 . 30 kW/m 2 size 12{1 "." "30"" kW/m" rSup { size 8{2} } } {} . 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?

Questions & Answers

where we get a research paper on Nano chemistry....?
Maira Reply
what are the products of Nano chemistry?
Maira Reply
There are lots of products of nano chemistry... Like nano coatings.....carbon fiber.. And lots of others..
learn
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
learn
Google
da
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Bhagvanji
Preparation and Applications of Nanomaterial for Drug Delivery
Hafiz Reply
revolt
da
Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
Jyoti Reply
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
Damian
yes that's correct
Professor
I think
Professor
Nasa has use it in the 60's, copper as water purification in the moon travel.
Alexandre
nanocopper obvius
Alexandre
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
Rafiq
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
Damian
How we are making nano material?
LITNING Reply
what is a peer
LITNING Reply
What is meant by 'nano scale'?
LITNING Reply
What is STMs full form?
LITNING
scanning tunneling microscope
Sahil
how nano science is used for hydrophobicity
Santosh
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
Rafiq
what is differents between GO and RGO?
Mahi
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
Rafiq
if virus is killing to make ARTIFICIAL DNA OF GRAPHENE FOR KILLED THE VIRUS .THIS IS OUR ASSUMPTION
Anam
analytical skills graphene is prepared to kill any type viruses .
Anam
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
Hafiz
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
Bob
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
why?
Adin
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
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Source:  OpenStax, Basic physics for medical imaging. OpenStax CNX. Feb 17, 2014 Download for free at http://legacy.cnx.org/content/col11630/1.1
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