How is the laser emission achieved in a Helium-Neon (He-Ne) laser_______________?
Show answer Hide answer
Answer: A. Ne only
Explanation
In a Helium-Neon laser, population inversion and subsequent laser emission occur exclusively in the Neon atoms. Helium atoms serve an auxiliary role by absorbing electrical energy and colliding with Neon atoms. Thus, laser light emission is produced directly by the energy level transitions of Neon. Helium-Neon lasers are continuous-wave gas lasers operating typically at a wavelength of 632.8 nanometers. Population inversion is a non-equilibrium state where more atoms occupy higher energy states than lower ones. Collisional excitation transfers energy efficiently between different gas atoms inside the laser tube.
He-Ne lasers are widely used in laboratory interferometry, barcode scanners, and alignment tools. Understanding gas laser mechanics helps engineers design efficient optical sources for industry. Helium-Neon systems provided some of the earliest stable demonstrations of continuous laser light. Ne only correctly identifies the active medium responsible for the actual laser emission. He-Ne both incorrectly suggests that both gas species contribute directly to the laser transition. Electrons of He ignores the fact that Helium merely transfers excitation energy to Neon.
Related questions
Q1. Mechanical work reaches its maximum value when the angle between force F and displacement vector d equals______________________?
Show answer Hide answer
Answer: D. 0°
Mechanical work formula includes the cosine of the angle between vectors. The cosine of zero degrees evaluates to the maximum value of one. Therefore, parallel force and displacement vectors produce maximum work. Work is...
Q2. What precisely are X-rays________________?
Show answer Hide answer
Answer: C. high energy photons
X-rays are packets of electromagnetic energy classified specifically as high-energy photons. Unlike electrons, photons possess no rest mass and travel at the speed of light. Wilhelm Röntgen discovered these mysterious ra...
Q3. The dimensional formula of work corresponds directly to that of__________________?
Show answer Hide answer
Answer: A. torque
Work is calculated as force multiplied by displacement distance along its line. Torque is calculated as force multiplied by perpendicular lever arm distance. Both physical quantities share the exact same dimensional form...
Q4. In their fundamental nature, X-rays share similarities with_______________?
Show answer Hide answer
Answer: C. γ-rays
X-rays and gamma rays are both forms of high energy electromagnetic radiation. They share identical fundamental wave and particle characteristics in physics. Their primary difference lies in their origin from atomic elec...
Q5. An instrument's zero error is classified as what kind of_________________?
Show answer Hide answer
Answer: C. Systematic error
A zero error is a consistent, reproducible flaw inherent to a measuring instrument's calibration, categorizing it as a systematic error. Because the offset remains constant across repeated trials, it shifts every recorde...
Q6. Which substance exhibits the widest forbidden energy gap ?
Show answer Hide answer
Answer: A. insulator
Insulators possess very wide forbidden energy gaps between valence and conduction bands. Thermal energy at room temperature cannot excite electrons across this wide gap. This absence of free charge carriers prevents elec...