lab02-2

When an electron moves from the n=5 orbit  to the n=4 orbit of a hydrogen atom, a photon of light is emitted a. What is the energy of this photon, in joules? b. What is the frequency of this radiation, in hertz? c. What is the wavelength of this radiation, in nanometers?

Why is it useful to create an assembly of very slow-moving cold atoms?A. The atoms can be more easily observed at slow speeds.B. Lowering the temperature this way permits isotopes that normally decay in very short times to persist long enough to be studied.C. At low speeds the quantum nature of the atoms becomes more apparent, and new forms of matter emerge.D. At low speeds the quantum nature of the atoms becomes less important, and they appear more like classical particles.

Thermal neutrons are produced by a fission nuclear reactor. The temperature of the neutrons is about room temperature, T 2 299 K. The kinetic energy of the neutron is E = kgT, where kp = 1.38 x 10–23 J/K is the Boltzmann constant. The mass of a neutron is m, = 1.67 x 10-27 kg. Part 1) Calculate the de Broglie wavelength of a thermal neutron. nm Part 2) The highest energy photons ever observed are y-rays with energies up to 311 trillion electron volts, Ey = 311 × 102 eV. The rays come from the Crab nebula, the remnant of a supernova explosion. Calculate the wavelength of these photons. m Part 3) A position uncertainty of an electron in a hydrogen atom is about size of the atom, which is Aæ = 0.500 Å = 0.500 × 10–10 m. Using the Heisenberg uncertainty relation, Ap Ax = , calculate the related kinetic energy (zero motion energy): (Ap? 2m E = 2m The electron mass is m = :0.910 x 10-30 kg. E eV

The mass of an electron is 9.11  10-31 kg.A.) If the wavelength of an electron is 4.67  10-7 m, how fast is it moving?1557.457391 m/s B.) If an electron has a speed equal to 5.30  106 m/s, what is its wavelength?1.37232566e-10 m

Solid State physics question

QUESTION 10 What is the the energy (in kj/mol of photons) of gamma ray radiation that has a frequency of 7.339e+19 Hz? The speed of light is 3.00x10 m/s and Planck's constant is 6.626x10 34 J*s. Click Save and Submit to save and submit. Click Save All Answers to save all answers. Save LIC AvAMUthima 774 508 29 tv MacBook Pro 2$ % 3 4 5 6 8

7. Borg ships are cubical. A Borg ship is approaching earth. According to an observer on earth, the Borg ship is 1000 m high, 1000 m wide, and has a depth of 200 m. Earth launches a photon torpedo to destroy the Borg ship. The torpedo is launched from earth with a velocity of 0.99. The torpedo was set on earth to go off in 2 hr. 09 ce 1000 m Earth 200m a) With what velocity is the Borg ship approaching earth? b) What is the speed of the torpedo as measured by an observer on the Borg ship? ) According to an observer on the Borg ship, how long will it take the torpedo to explode?

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a.) Find the frequency in Hertz of radiation with energy of 2.179 x 10-18 J per photon. b.) What frequency of light would be needed to make an electron in a Hydrogen atom jump from n=1 to n=3? c.) A spectral line is measured to have a wavelenght of 1000nm. Is this within the Balmer series?

1.6 X kg-m/s. What is the de Broglie wavelength of the electrons? 7. During a certain experiment, the de Broglie wavelength of an electron is 670 nm = 6.7 x 10-7 m, which is the same as the wavelength of red light. How fast is the electron moving? 8. If a proton were traveling the same speed as cle

A furnace emits radiation at 2000 K. Treating it as black body radiation, calculate the wavelength at which the emission is maximum. a.) 1.449 x 10 ^ -6 m b.) 2.449 x 10 ^ -6 m c.) 3.449 x 10 ^ -6 m d.) 4.449 x10 ^ -6 m

4C. Electrons in one electron beam have a greater speed than those in another. Which electrons have the longer de Broglie wavelength? In your notes, use the appropriate formula to support your answer. ○ The relatively FASTER electron beam ○ The relatively SLOWER electron beam О The electron beams have the same de Broglie wavelength because they travel at the speed of light

A 83.0 kg athlete running a "4-minute mile" (i.e. 4.00 min/mile) _____ nm an electron (me = 9.10939 1028 g) moving at 3.90 106 m/s in an electron microscope _____ nm.

What is the frequency of the emitted photon when an electron in a hydrogen atom jumps from n = 5 to n = 2 state? a) 2.30*106 Hz b) 6.91*1016 Hz c) 6.91*1014 Hz    d) none of these.

6. Some of the energy levels of the mercury atoms are shown in figure below. Energy (eV) 1,6 3.7 5.5 10.4 Ground state a) How much energy (in Joule) is required to raise an electron from the ground state to third excitation level? b) What is the ionization energy of mercury?

1. Show that the frequency of the photon emitted by a hydrogen atom in going from state n + 1 to n is always intermediate between the frequencies of revolution of the electron in the two orbits. 2. A µ − muon is in the n = 2 state of a muonic atom whose nucleus is a proton.Find the wavelength of the photon emitted when the muonic atom drops to its ground state. Consider nuclear motion in your calculation. Values for certain constants:h = 6.626 × 10 −34 Js, E 1 = −13.6 eV, r 1 = 5.29 × 10 −11 m, 1 eV = 1.602 × 10 −19 J.

Identical light beams (i.e. same intensity and wavelength) strike three different metals, all of which emit electrons. Part A: Which metal results in the fastest ejected electrons? A) Lead B) Copper C) Nickel D) The maximum speed is the same for all metals   Part B: Which metal results in the least number of ejected electrons per second? A) Copper B) Nickel C) Lead D) The number of the ejected electrons is the same for all 3 metals     **Can you explain to me, in Part A, why Lead is the metal the results in the fastest ejected electrons? In Part B, why the number of ejected electrons is the same for all 3 metals? Thank you.

Given that 0.750 mol of a particular atom all release an identical photon, resulting in a total energy change of -176.0 kJ. Answer the following: (Hint: n does not equal 1 here) a. What is the wavelength of the photons released? b. What is the frequency of these photons? c. What region of the electromagnetic spectrum is this emitted photon in?

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