brodidit for students
Atomic spectra
Class 12 · Physics · 5 questions
Name: ____________________ Date: ____________
In the Bohr model, electrons orbit in:
- A Any orbit
- B Elliptical only
- C Straight lines
- D Fixed energy levels
The Lyman series corresponds to transitions ending at:
- A n = 3
- B n = 1
- C n = 4
- D n = 2
X rays are produced when fast electrons:
- A Are slowed in water only
- B Hit a metal target
- C Are reflected by glass
- D Pass through air
LASER stands for light amplification by:
- A Stimulated emission of radiation
- B Selective emission of rays
- C Spontaneous emission of rays
- D Stimulated electrons
The wavelength emitted when an atom jumps between levels depends on:
- A The energy difference of the levels
- B The temperature only
- C Its mass
- D The atom's colour
Answer key
1. D, 2. B, 3. B, 4. A, 5. A
Only certain orbits with fixed energies are allowed.
Lyman lines are in the ultraviolet and end at n = 1.
Sudden deceleration of electrons in a target produces X rays.
This is the meaning of the word.
E = h c / wavelength equals the energy difference.