Question

How is light amplified in a laser?

Photons “leak” through a partially reflecting mirror, causing them to travel in step.
Integrated circuits in a laser amplify the sound produced by photon emission.
Photons collide with gas particles, multiply, and reflect back and forth in a tube.
Electric current is amplified and directed into gas particles, which emit photons.

Answer 1

None of these options accurately explains how light is amplified in a laser. The correct answer is: Electric current is amplified and directed into a material (typically a crystal or gas) that has the ability to amplify light waves through stimulated emission. This process causes photons to be emitted in step with each other, creating a coherent beam of light that is further amplified as it repeatedly reflects back and forth between the mirrors at either end of the laser cavity.