Atomic Physics ...

Directions: The following question has four choices out of which ONLY ONE is correct.

De Broglie used Einstein's special theory of relatively together with Plank's quantum theory to establish the wave property of particles. He gave fundamental relationship ; where and p is wavelength and momentum respectively and h is Plank's constant. A de-Broglile wave associated with an electron can form a standing wave between the atoms arranged in a one dimensional array with node at each of the atomic sites. A standing wave is formed when the distance between the atoms of any array is d = 3A^o_. A similar standing wave is again formed if d = 3.5 A^o but not for any intermediate value of d.
For thermal neutron at ordinary temperature, energy is given by relation E = kT, where K is Boltzman constant mass of Neutron is 1.67 10^–23 g.

The least value of d for which standing wave can be formed is

Directions: The following question has four choices out of which ONLY ONE is correct.

De Broglie used Einstein's special theory of relatively together with Plank's quantum theory to establish the wave property of particles. He gave fundamental relationship ; where and p is wavelength and momentum respectively and h is Plank's constant. A de-Broglile wave associated with an electron can form a standing wave between the atoms arranged in a one dimensional array with node at each of the atomic sites. A standing wave is formed when distance between the atoms of any array is d = 3A^o. A similar standing wave is again formed if d = 3.5 A^o but not for any intermediate value of d.
For thermal neutron at ordinary temperature, energy is given by relation E = kT, where K is Boltzman's constant mass of Neutron is 1.6710^–23 g.

The energy of electron (in eV) to form this standing wave is

De Broglie used Einstein's special theory of relatively together with Plank's quantum theory to establish the wave property of particles. He gave fundamental relationship ; where and p is wavelength and momentum respectively and h is Plank's constant. A de-Broglile wave associated with an electron can form a standing wave between the atoms arranged in a one-dimensional array with node at each of the atomic sites. A standing wave is formed when the distance between the atom's of any array is d = 3A^o. A similar standing wave is again formed if d = 3.5 A^o but not for any intermediate value of d.

For thermal neutron at ordinary temperature, energy is given by relation E = kT, where K is Boltzman's constant and mass of neutron is 1.6710^–23 g.

De-Broglie wavelength associated with neutrons in thermal equilibrium with matter at 27^oC is

Directions: The following question has four choices out of which ONLY ONE is correct.

The X-ray emission line of tungsten occurs at= 0.021 nm. What is the energy difference between K and L levels in its atoms?

Two radioactive materials X₁ and X₂ have decay constants 10 and _^, respectively. If initially they have the same number of nuclei, then the ratio of the number of nuclei of X₁ to that of X₂ will be 1/e after what time period?

A freshly prepared radioactive source of half life 2h emits radiation of intensity, which is 64 times of the permissible safe level. The minimum time after which it would be possible to work safely with this source is

Directions: The following question has five choices out of which ONLY ONE is correct.

What is the average K.E of a gas molecule at a temperature of 300 K?: (Boltsmann constant = 1.3810^–23 JK^–1)

Directions: The following question has five choices out of which ONLY ONE is correct.

The activity of a radioactive element decreases to one third of the original activity A₀ in a period 9 years. After a further lapse of 9 years, its activity will be

Two nucleons are at a separation of 1 Fermi. The net force between them is F₁ if both are neutrons, F₂ if both are protons and F₃ if one is proton and the other is a neutron. Which of the following is correct?

Directions: The following question has five choices out of which ONLY ONE is correct.

Given below is a Cs. of electromagnetic spectrum and its mode of production. Which one does not match?

A proton accelerated through a potential V has de-Broglie wavelength . Then, the de-Broglie wavelength of an -particle, when accelerated through the same potential V, is

Directions: The following question has five choices out of which ONLY ONE is correct.

Two radioactive samples have decay constants 15 x and 3 x. If they have the same number of nuclei initially, the ratio of number of nuclei after a time is

Directions: The following question has five choices out of which ONLY ONE is correct.

If the mass defect of ₈O¹⁶ nucleus is 0.128 amu, then the binding energy per nucleon of oxygen is

¹⁴N₇ is bombarded with ⁴He₂. The resulting nucleus is ¹⁷O₈ with the emission of a/an

a-particles of energy 400 KeV are bombarded on nucleus of ₈₂Pb. In scattering of a -particles, its minimum distance from nucleus will be