The ionization energy of Li⁺⁺ is equal to
The ionization energy of Li⁺⁺ is equal to
Options
(a) 9hcR (b) 6hcR (c) 2hcR (d) hcR
Correct Answer:
9hcR
Explanation:
Ionisation energy of Li⁺⁺ = 9hcR
Ionisation energy = RchZ² = Rhc(3)² = […]
Dual Nature of Matter and Radiation
The threshold frequency for a metallic surface corresponds to an energy of 6.2 eV,
The threshold frequency for a metallic surface corresponds to an energy of 6.2 eV, and the stopping potential for a radiation incident on this surface 5 V. The incident radiation lies in
Options
If alpha, beta and gamma rays carry same momentum, which has the longest
If alpha, beta and gamma rays carry same momentum, which has the longest wavelength
Options
(a) Alpha rays (b) Beta rays (c) Gamma rays (d) None, all have same wavelength
Correct Answer:
None, […]
Photoelectric current from a given photocell will depend upon
Photoelectric current from a given photocell will depend upon
Options
(a) Number of photons striking per second (b) Frequency of incident photon (c) Material of the target (d) None of the above
Correct […]
Which one of the following statements is WRONG in the context of X-rays generated
Which one of the following statements is WRONG in the context of X-rays generated from a X-ray tube?
Options
(a) Wavelength of characteristic X-rays decreases when the atomic number of the target increases […]
A photocell employs photoelectric effect to convert
A photocell employs photoelectric effect to convert
Options
(a) Change in the frequency of light into a change in the electric current (b) Change in the frequency of light into a change in […]
Characteristic X-rays are produced due to
Characteristic X-rays are produced due to
Options
(a) Transfer of momentum in collision of electrons with target atoms (b) Transition of electrons from higher to lower electronic orbits in an atom (c) Heating […]
Light is emitted when
Light is emitted when
Options
(a) Electron make an transition from higher orbit to lower orbit (b) Electron make an transition from lower to higher orbit (c) Electron rotates in its own orbit […]
When photons of energy hν fall on an aluminium plate (of work function E₀),
When photons of energy hν fall on an aluminium plate (of work function E₀), photoelectrons of maximum kinetic energy K are ejected. If the frequency of radiation is doubled, the maximum kinetic energy of the […]
Cathode rays are produced when the pressure is of the order of
Cathode rays are produced when the pressure is of the order of
Options
(a) 2 cm of Hg (b) 0.1 cm of Hg (c) 0.01 mm of Hg (d) 1μm of Hg
Correct […]