Topic :: Quantum





Quantum Interview Questions
Questions Answers Views Company eMail

How can we use quantum properties in cryptography ?

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What is quantum computing ?

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What is quantum cryptography ?

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What is an advantage of a large scheduling quantum? What is a disadvantage?

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Question 99 - (a) The quantum number m is given by m = -s, -s + 1. If s = 0.5, find the values of m. (b) | T > = (cos T) | V > + (sin T) | H >. The V and H states form a basis for all polarizations. Let cos T = 0.8. (i) If (sin T)(sin T) + (cos T)(cos T) = 1, find the value of sin T. (ii) For | T > = a | V > + b | H >, where a x a represents the probability of | V > and b x b represents the probability of | H >. Which one is more abundant, | V > or | H >? (iii) Find the value of T without using any mathematical tools.

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Question 105 - In a rigid rotor model in quantum chemistry, the moment of inertia I is given by an Equation E as I = Ma x La x La + Mc x Lc x Lc = m x L x L, where m = (Ma x Mc) / (Ma + Mc) and L = La + Lc, m is the reduced mass, Ma is the mass of a, Mc is the mass of c, La is the radius of a from point O, Lc is the radius of c from point O. Prove by simplest method that Equation E is wrong.

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Question 104 - In photoelectrical effect analysis of quantum chemistry, let E = kinetic energy of electron, p = intensity of UV light, f = frequency of UV light. According to Classical Theory, E = c for all values of f, E = mp. According to Quantum Theory, E = c for all values of p, E = mf + c. In a graph, m and c are constants where m is slope and c is y intercept. If m = 2 and c = 3 with similar value of E : (a) find the value of p according to Classical Theory; (b) find the value of f according to Quantum Theory.

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Question 107 - In N + 1 Rule in Quantum Chemistry, whenever a spin 1 / 2 nucleus is adjacent to N other nuclei, it is split into N + 1 distinct peaks. In 1 peak or singlet, there is only 1 magnitude. In 2 peaks or doublet, the ratio of magnitude of each peak is 1 : 1. In 3 peaks or triplet, the ratio of magnitude of each peak is 1 : 2 : 1. In 4 peaks or quartet, the ratio of magnitude of each peak is 1 : 3 : 3 : 1. In 5 peaks or quintet, the ratio of magnitude of each peak is 1 : 4 : 6 : 4 : 1. (a) By using binomial coefficients or Triangle of Pascal find the ratio of magnitude of each peak if 6 peaks exists. (b) How many adjacent nuclei are available in a spin 1 / 2 nucleus in such situation of 6 peaks?

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Question 109 - (a) Acceptable wavefunction in quantum mechanics in the range of : negative infinity < x < positive infinity, vanishes at least at one boundary. Which of the following is the wavefunction or are the wavefunctions of acceptable theory : P = x, P = | x |, P = sin x, P = exp (-x), P = exp (-| x |)? State the reason. (b) Let linear momentum operator P = -ih d / dz. The wavefunction is S = exp (-ikz) where i x i = -1, k and h are constants. Find the linear momentum of such wavefunction by using the term P x S.

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ENGINEERING PHYSICS - EXAMPLE 30.3 : (a) The quantum number m is given by m = -s, -s + 1. If s = 0.5, find the values of m. (b) | T > = (cos T) | V > + (sin T) | H >. The V and H states form a basis for all polarizations. Let cos T = 0.8. (i) If (sin T)(sin T) + (cos T)(cos T) = 1, find the value of sin T. (ii) For | T > = a | V > + b | H >, where a x a represents the probability of | V > and b x b represents the probability of | H >. Which one is more abundant, | V > or | H >? (iii) Find the value of T without using any mathematical tools.

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QUANTUM CHEMISTRY AND CHEMICAL ENGINEERING - EXAMPLE 31.1 : As an approximation, let v = Zc / 137 where v is the radial velocity for 1 s electron of an element, c is the speed of light, Z is the atomic number. For gold with Z = 79, find the radial velocity of its 1 s electron, in term of c and percentage of the speed of light. (b) As an approximation, let A x A = 1 - Z x Z / 18769 where A is the ratio of the relativistic and non-relativistic Bohr radius. Find the value of A.

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QUANTUM CHEMISTRY AND CHEMICAL ENGINEERING - EXAMPLE 31.2 : (a) Let | - > = 1 | x > + 0 | y >, | | > = 0 | x > + 1 | y >. Find the value of 2 | x > + 3 | y > in term of | - > and | | >. (b) Let m to be the reduced mass. Find the value of m in term of Ma and Mb where 1 / m = 1 / Ma + 1 / Mb.

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QUANTUM CHEMISTRY AND CHEMICAL ENGINEERING - EXAMPLE 31.3 : In photoelectrical effect analysis of quantum chemistry, let E = kinetic energy of electron, p = intensity of UV light, f = frequency of UV light. According to Classical Theory, E = c for all values of f, E = mp. According to Quantum Theory, E = c for all values of p, E = mf + c. In a graph, m and c are constants where m is slope and c is y intercept. If m = 2 and c = 3 with similar value of E : (a) find the value of p according to Classical Theory; (b) find the value of f according to Quantum Theory.

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QUANTUM CHEMISTRY AND CHEMICAL ENGINEERING - EXAMPLE 31.4 : In a rigid rotor model in quantum chemistry, the moment of inertia I is given by an Equation E as I = Ma x La x La + Mc x Lc x Lc = m x L x L, where m = (Ma x Mc) / (Ma + Mc) and L = La + Lc, m is the reduced mass, Ma is the mass of a, Mc is the mass of c, La is the radius of a from point O, Lc is the radius of c from point O. Prove by simplest method that Equation E is wrong.

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QUANTUM CHEMISTRY AND CHEMICAL ENGINEERING - EXAMPLE 31.5 : In a wavefunction, let P(x) = A cos kx + B sin kx. By using the boundary conditions of x = 0 and x = l, where P(0) = P(l) = 0, prove by mathematical calculation that P(x) = B sin (npx / l) where p = 22 / 7 approximately, n is a rounded number. A, B and k are constants.

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Un-Answered Questions { Quantum }

How can we use quantum properties in cryptography ?

1313


Measurements of a certain system have shown that the average process runs for a time T before blocking on I/O. A process switch requires a time S, which is effectively wasted (overhead). The CPU’s efficiency is the fraction of its time its spends executing user programs, i.e., executing user processes. For round robin scheduling with quantum Q, give a formula for the CPU efficiency for each of the following: (a) Q = ∞ (b) Q > S + T (c) S

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what is the significance of the hrmite and polynomial polynomials in quantum phyics.

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Write a program to implement a round robin scheduler and calculate the average waiting time.Arrival time, burst time, time quantum, and no. of processes should be the inputs.

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What advantage is there in having different time-quantum sizes on different levels of a multilevel queuing system?

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What is the quantum cryptography?

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Whar are the different parts of the x-ray radiation intensity graph? : quantum physics

547


Explain the different parts of the x-ray radiation intensity graph? : quantum physics

547


What are the 4 results of the photoelectric effect experiments? : quantum physics

464


Explain the difference between emission and absorption line spectra. : quantum physics

509


What is meant by energy spectrum of a black body? : quantum physics

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Explain planck’s hypothesis? : quantum physics

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Explain qualitatively the phenomenon of quantum tunneling of an electron across a potential barrier? : quantum physics

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What is the essence of quantum physics? What makes it so different from classical physics? : quantum physics

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What are the characteristics of black body? : quantum physics

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