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Derive the approximate form of Heisenberg's uncertainty principle for energy and time,
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- A) Calculate the de Broglie wavelength of a neutron (mn = 1.67493×10-27 kg) moving at one six hundredth of the speed of light (c/600). (Enter at least 4 significant figures.) B) Calculate the velocity of an electron (me = 9.10939×10-31 kg) having a de Broglie wavelength of 230.1 pm.arrow_forwardSuppose a laser pulse has an average duration of 5.00 femtoseconds and an average energy of 1.81 eV, and it has an uncertainty of 13.8%. What is the highest energy you can observe for a photon in the pulse? (in eV)arrow_forwardThe normalized wavefunction of an electron in a linear accelerator is ψ = (cos χ)eikx + (sin χ)e–ikx, where χ (chi) is a parameter. (a) What is the probability that the electron will be found with a linear momentum (a) +kħ, (b) −kħ? (c) What form would the wavefunction have if it were 90 per cent certain that the electron had linear momentum +kħ? (d) Evaluate the kinetic energy of the electron.arrow_forward
- The velocity of an electron is known to be 1.000×105 m/s, with an uncertainty of Av = 1.00×102 m/s. (a) What is the minimum uncertainty in the electron's position, Av, in meters? (b) How does this compare to the de Broglie wavelength of the electron? (c) One of your professors (m = 75.0 kg) is pacing at the front of the classroom, and you measure their velocity to an uncertainty of Av = 0.100 m/s. What is the minimum uncertainty in a measurement of their position? (d) How does this compare to the height of your professor?arrow_forwardassume that an electron is moving along the x-axis and that you measure its speed to be 20.5*10^6m/s, which can be known with of precision of 0.50%. what is the minimum uncertainty (as allowed by the uncertainty principle in quantum theory )with which you can simultaneously measure the position of the electron along the x-axis?arrow_forwardQ:-3(a)-An electron moves in the x direction with a speed of 2.8 x 106 m/s. We can measure its speed to a precision of 2 %. With what precision can we simultaneously measure its x coordinate? (b)- Repeat the calculations of the previous example in the case of a pitched baseball (m = 0.135 kg) moving at a speed of (44.5 ms). Again assume that its speed can be measured to a precision of 2%arrow_forward
- A photon with wavelength X scatters off an electron at rest, at an angle with the incident direction. The Compton wavelength of the electron Ac = 0.0024 nm. a) For λ = 0.0006 nm and 0 = 53 degrees, find the wavelength X' of the scattered photon in nanometres. b) Obtain a formula for the energy of the electron Ee after collision, in terms of the universal constants h, c and the variables X, X' and Ac. The answer must be expressed in terms of these variables only. (Please enter an algebraic expression using latex format; do not input any numerical values) c) Using the energy conservation condition, find the value of the electron energy Ee after scattering in units of keV. d) Write an algebraic expression for the electron's momentum pe in terms of its energy Ee, its mass me and the speed of light c. e) What is the de Broglie wavelength of the scattered electron ? Express your answer in terms of Ee, me, and X and c. f) Find the value of the de Broglie wavelength of the scattered electron…arrow_forwardThe kilogram has been redefined based on Planck's constant (h) and a sphere of pure crystalline silicon: 8AsiVsphere Msphere = 2h 13 ст-а? The terms (with their relative uncertainties) are: (1) Planck's constant h (zero uncertainty as it is defined exactly); (2) the bracketed term including accurately known Rydberg constant R, speed of light c, mass of electron (me), and fine structure constant a, with a combined uncertainty of +4.7 × 10-8%; (3) atomic mass Asi for the 28 Si-enriched silicon (+5.4 x 10-7%); (4) volume of the Si sphere (+2.0 × 10-6%) and (5) crystal lattice parameter I (+1.84 x 10-7%). There are exactly eight atoms per unit cell in the sphere. Compute the relative uncertainty of myphere- To find the uncertainty of l, use the function y = x“, for which the uncertainty is propagated using %e, = a(%e,). relative uncertainty of msphere: % The mass of the sphere of pure silicon (999.698 336 5 g) must also be corrected for defects in the crystal lattice ( mdefects = 3.8…arrow_forwardImagine another universe in which the value of Planck’s constant is 0.0663 J . s, but in which the physical laws and all other physical constants are the same as in our universe. In this universe, two physics students are playing catch. They are 12 m apart, and one throws a 0.25 kg ball directly toward the other with a speed of 6.0 m/s. (a) What is the uncertainty in the ball’s horizontal momentum, in a direction perpendicular to that in which it is being thrown, if the student throwing the ball knows that it is located within a cube with volume 125 cm3 at the time she throws it? (b) By what horizontal distance could the ball miss the second student?arrow_forward
- Through what potential difference ΔVΔV must electrons be accelerated (from rest) so that they will have the same wavelength as an x-ray of wavelength 0.130 nmnm? Use 6.626×10−34 J⋅sJ⋅s for Planck's constant, 9.109×10−31 kgkg for the mass of an electron, and 1.602×10−19 CC for the charge on an electron. Express your answer using three significant figures. =89.0 V Through what potential difference ΔVΔV must electrons be accelerated so they will have the same energy as the x-ray in Part A? Use 6.626×10−34 J⋅sJ⋅s for Planck's constant, 3.00×108 m/sm/s for the speed of light in a vacuum, and 1.602×10−19 CC for the charge on an electron. Express your answer using three significant figures. Second question is what I need help on! Thanks!arrow_forwardAn electron is confined to a region of space of the size of an atom (0.1 nm). (a) What is the uncertainty in the momentum of the electron? (b) What is the kinetic energy of an electron with a momentum equal to Ap? (c) Does this give a reasonable value for the kinetic energy of an electron in an atom?arrow_forwardThe moon has a mass of 7.35 * 1022 kg, and the length of a sidereal day is 27.3 days. (a) Estimate the de Broglie wavelength of the moon in its orbit around the earth. (b) Using Mearth for the mass of the earth and Mmoon for the mass of the moon, we can use Newton’s law of gravitation to determine the radius of the moon’s orbit in terms of an integer-valued quantum number m as Rm = m2amoon, where amoon is the analog of the Bohr radius for the earth–moon gravitational system. Determine amoon in terms of Newton’s constant G, Planck’s constant h, and the masses Mearth and Mmoon. (c) The mass of the earth is Mearth = 5.97 * 1024 kg. Estimate the numerical value of amoon. (d) The radius of the moon’s orbit is 3.84 * 108 m. Estimate the moon’s quantum number m. (e) The quantized energy levels of the moon are given by E = -E0/m2. Estimate the quantum ground-state energy E0 of the moon.arrow_forward
- Principles of Physics: A Calculus-Based TextPhysicsISBN:9781133104261Author:Raymond A. Serway, John W. JewettPublisher:Cengage Learning