Beta rays emitted by a radioactive material are.
Light of wavelength λph falls on a cathode plate inside a vacuum tube as shown in the figure. The work function of the cathode surface is ϕ and the anode is a wire mesh of conducting material kept at a distance d from the cathode. A potential difference V is maintained between the electrodes. If the minimum de Broglie wavelength of the electrons passing through the anode is λθ, which of the following statement(s) is (are) true?
16
Sep
Light of wavelength λph falls on a cathode plate inside a vacuum tube as shown in the figure. The work function of the cathode surface is ϕ and the anode is a wire mesh of conducting material kept at a distance d from the cathode. A potential difference V is maintained between the electrodes. If [...]
Wavelengths belonging to Balmer series lying in the range of 450 nm to 750 nm were used to eject photoelectrons from a metal surface whose work function is 2.0 eV. Find ( in eV ) the maximum kinetic energy of the emitted photoelectrons. (“Take hc = 1242 eV nm.”)
16
Sep
Wavelengths belonging to Balmer series lying in the range of 450 nm to 750 nm were used to eject photoelectrons from a metal surface whose work function is 2.0 eV. Find ( in eV ) the maximum kinetic energy of the emitted photoelectrons. (“Take hc = 1242 eV nm.”) Beta rays emitted by a radioactive [...]
A hydrogen-like atom (described by the Bohr model) is observed to emit six wavelengths, originating from all possible transitions between a group of levels. These levels have energies between –0.85 eV and –0.544 eV (including both these values). (a) Find the atomic number of the atom. (b) Calculate the smallest wavelength emitted in these transitions. (Take hc = 1240 eV.nm. Ground state energy of hydrogen atom = – 13.6 eV)
16
Sep
A hydrogen-like atom (described by the Bohr model) is observed to emit six wavelengths, originating from all possible transitions between a group of levels. These levels have energies between –0.85 eV and –0.544 eV (including both these values). (a) Find the atomic number of the atom. (b) Calculate the smallest wavelength emitted in these transitions. [...]
A nucleus at rest undergoes alpha decay emitting an alpha particle of de Broglie wavelength lemba = 5.76 * 10^-15 m. If the mass of the daughter nucleus is 223.610 amu and that of the alpha particle is 4.002 amu, determine the total kinetic energy in a final state. Hence obtain the mass of the parent nucleus in amu.
16
Sep
A nucleus at rest undergoes alpha decay emitting an alpha particle of de Broglie wavelength lemba = 5.76 * 10^-15 m. If the mass of the daughter nucleus is 223.610 amu and that of the alpha particle is 4.002 amu, determine the total kinetic energy in a final state. Hence obtain the mass of the [...]
Assume that the de-Broglie was associated with an electron can forma standing wave between the atoms arranged in a one dimensional array with nodes at each of the atomic sites. It is found that one such standing wave is formed if the distance d between the atoms of the array is 2 Å. A similar standing wave is again formed if d is increased to 2.5 Å but not for any intermediate value of d. Find the energy of the electron in eV and the least value of d for which the standing wave of the type described above can form.
16
Sep
Assume that the de-Broglie was associated with an electron can forma standing wave between the atoms arranged in a one dimensional array with nodes at each of the atomic sites. It is found that one such standing wave is formed if the distance d between the atoms of the array is 2 Å. A similar [...]
A small quantity of solution containing 24Na radionuclide (half-life 15 h) of activity 1.0 microcurie is injected into the blood of a person. A sample of the blood of volume 1cm^3 taken after 5 h shows an activity of 296 disintegrations min^−1 . Determine the total volume of blood in the body of the person. Assume that the radioactivity solution mixes uniformly in the blood of the person. (1 curie =3.7×10^10 disintegrations^−1 )
16
Sep
A small quantity of solution containing 24Na radionuclide (half-life 15 h) of activity 1.0 microcurie is injected into the blood of a person. A sample of the blood of volume 1cm^3 taken after 5 h shows an activity of 296 disintegrations min^−1 . Determine the total volume of blood in the body of the person. [...]
A hydrogen like atom(atomic number Z) is in a higher excited state of quantum number n. The excited atom can make a transition to the first excited state by successively emitting two photons of energy 10.2 and 17.0 eV respectively. Alternatively, the atom from the same excited state can make a transition to the second excited state by successively emitting two photons of energies 4.25 eV and 5.95 eV respectively. Determine the values of n and Z. (lonization energy of H atom= 13.6 eV)
16
Sep
A hydrogen like atom(atomic number Z) is in a higher excited state of quantum number n. The excited atom can make a transition to the first excited state by successively emitting two photons of energy 10.2 and 17.0 eV respectively. Alternatively, the atom from the same excited state can make a transition to the second [...]
Light from a discharge tube containing hydrogen atoms falls on the surface of a piece of sodium. The kinetic energy of the fastest photo-electrons emitted from sodium is 0.73 eV. The work function for sodium is 1.82 eV. Find:
16
Sep
Light from a discharge tube containing hydrogen atoms falls on the surface of a piece of sodium. The kinetic energy of the fastest photo-electrons emitted from sodium is 0.73 eV. The work function for sodium is 1.82 eV. Find: Beta rays emitted by a radioactive material are. September 16, 2021 Category: Chapter 18 - Atoms [...]
Electrons in hydrogen like atom (Z=3) make transition from the fifth to the fourth orbit and from the fourth to the third orbit. The resulting radiation are incident normally on a metal plate and ejects photo-electrons. The stopping potential for the photo-electrons ejected by the shorter wavelength is 3.95 eV. Calculate the work function of the metal and stopping potential for the photo-electrons ejected by the longer wavelength.(R H =1.094 × 10^7 m^−1 )
16
Sep
Electrons in hydrogen like atom (Z=3) make transition from the fifth to the fourth orbit and from the fourth to the third orbit. The resulting radiation are incident normally on a metal plate and ejects photo-electrons. The stopping potential for the photo-electrons ejected by the shorter wavelength is 3.95 eV. Calculate the work function of [...]
A beam of light has three wavelengths 4144 A o, 4972 A ˚ and 6216 A ˚ with a total intensity of 3.6×10^−3 Wm^−2 equally distributed amongst the three wavelengths. The beam falls normally on an area 1.0 cm^2 of a clean metallic surface of work function 2.3 eV. Assume that the there is no loss of light by reflection and that each energetically capable photon ejects one electron. Calculate a number of photoelectrons liberated in two seconds.
16
Sep
A beam of light has three wavelengths 4144 A o, 4972 A ˚ and 6216 A ˚ with a total intensity of 3.6×10^−3 Wm^−2 equally distributed amongst the three wavelengths. The beam falls normally on an area 1.0 cm^2 of a clean metallic surface of work function 2.3 eV. Assume that the there is no [...]