Hot gases don’t produce a continuous emission spectrum. Black hydrogen absorption lines are at the same wavelength as the bright hydrogen emission lines. Key fact Line emission spectra are ...

The black panels should block everything on the camera's right-side field of view. If using the hydrogen source, be sure to aim the camera at the red part of the excited gas. Turn off the lamp when ...

The first zero-emission, hydrogen-powered passenger train in the US, called the FLIRT H₂, will begin service later this year in southern California. The record-holding commuter train will ...