de Broglie wavelength and uncertainty principle

27 questions on de Broglie wavelength and uncertainty principle from the Atomic Structure chapter: 5 NEET level, 11 JEE Main, 11 JEE Advanced. Each one opens with its answer and solution.

• If the speed of a moving electron is doubled while its mass stays the same, its de Broglie wavelength NEET level
• A ball of mass 0.10 kg moves at 10 m s^-1. Taking h = 6.626x10^-34 J s, its de Broglie wavelength is closest to NEET level
• According to Heisenberg's uncertainty principle, if the position of a microscopic particle is measured with greater and greater precision, the uncertainty in it... NEET level
• An electron is accelerated from rest through a potential difference of 150 V. Using h = 6.626x10^-34 J s, m_e = 9.1x10^-31 kg and e = 1.6x10^-19 C, its de Brogl... NEET level
• A particle of mass m has kinetic energy K. Its de Broglie wavelength is NEET level
• An electron moves at 3.0x10^6 m s^-1. Use h = 6.626x10^-34 J s and m_e = 9.1x10^-31 kg. Its de Broglie wavelength is JEE Main level
• An electron and a proton have equal kinetic energies. Taking m_p = 1836 m_e, the ratio lambda_e/lambda_p is closest to JEE Main level
• A proton and an alpha-particle (mass 4 times that of a proton, charge 2e) are accelerated from rest through the same potential difference. The ratio lambda_p/la... JEE Main level
• Using the Bohr model with a_0 = 0.529 AA, the de Broglie wavelength of the electron in the n=2 orbit of hydrogen is closest to JEE Main level
• The uncertainty in position of an electron equals its own de Broglie wavelength. Using Delta x Delta p ge h/4pi, the minimum fractional uncertainty Delta v/v in... JEE Main level
• An electron is accelerated from rest through 250 V. Use h = 6.626x10^-34 J s, m_e = 9.1x10^-31 kg, e = 1.6x10^-19 C. Find its de Broglie wavelength in pm, to th... JEE Main level
• A thermal neutron (mass 1.675x10^-27 kg) has kinetic energy 0.040 eV. Use h = 6.626x10^-34 J s and 1 eV = 1.6x10^-19 J. Find its de Broglie wavelength in AA, to... JEE Main level
• The position of an electron is known to within 0.50 AA. Using Delta x Delta p = h/4pi, h = 6.626x10^-34 J s and m_e = 9.1x10^-31 kg, find the minimum uncertaint... JEE Main level
• Find the accelerating potential (in volts, nearest integer) needed to give an electron a de Broglie wavelength of 0.50 AA. Use h = 6.626x10^-34 J s, m_e = 9.1x1... JEE Main level
• Select the correct statements about the de Broglie wavelength lambda of material particles. JEE Main level
• Which of the following are consistent with Heisenberg's uncertainty principle Delta x Delta p ge h/4pi? JEE Main level
• In the Bohr model the electron wavelength in an orbit satisfies nlambda = 2pi r_n with r_n propto n^2/Z. The ratio of the electron's de Broglie wavelength in th... JEE Advanced level
• A photon and an electron each have a wavelength of 1.00 AA. Using h = 6.626x10^-34 J s, c = 3.0x10^8 m s^-1, m_e = 9.1x10^-31 kg and 1 eV = 1.6x10^-19 J, the ra... JEE Advanced level
• A deuteron (mass 2 u, charge +e) and an alpha-particle (mass 4 u, charge +2e) are both accelerated from rest through the same potential difference. The ratio la... JEE Advanced level
• Treat an electron as a standing wave in a one-dimensional box of length L (lambda = 2L/n) with E = p^2/2m. If the box length is doubled, the energy of the n=2 l... JEE Advanced level
• An electron is treated as a standing de Broglie wave in a one-dimensional box of length 0.50 nm with lambda = 2L/n and purely kinetic energy. Find the kinetic e... JEE Advanced level
• In the Bohr model of hydrogen, the circumference of an orbit equals nlambda and r_n = n^2 a_0 with a_0 = 0.529 AA. Find the de Broglie wavelength of the electro... JEE Advanced level
• An electron is confined within Delta x = 0.20 nm. Take the minimum momentum uncertainty Delta p = h/(4piDelta x) and estimate the least kinetic energy as (Delta... JEE Advanced level
• A bullet of mass 5.0 g moves at 400 m s^-1, with the speed known to within 0.0010 %. Using Delta x Delta p = h/4pi with h = 6.626x10^-34 J s, find the minimum u... JEE Advanced level
• Two particles A and B have masses m_A = 4m_B. Select the correct statements about their de Broglie wavelengths. JEE Advanced level
• In the Bohr model, nlambda = 2pi r_n and lambda propto n/Z for hydrogen-like species. Select the correct statements. JEE Advanced level
• Use h = 6.626x10^-34 J s and m_e = 9.1x10^-31 kg with Delta x Delta p = h/4pi. Select the correct statements. JEE Advanced level