A person fires a starting pistol. A distant observer stood 200 metres away (measured using a 20 m tape measure or trundle wheel) records the time between seeing the flash of light from the ...

The Zumwalt-class stealth destroyers will be mounted with experimental hypersonic weapon systems, but what makes this technology so lethal?

Although sound travels quite fast, it is still possible to measure its speed in air. To do this, you need to measure the time it takes a sound to travel a measured distance. To reduce errors ...