Add Yahoo as a preferred source to see more of our stories on Google. The Doomsday Clock is a physical clock, but it does not tell time. It's meant to symbolize how close humanity is to destroying ...

The tick-tick sound comes from the movement of gears and parts inside the clock. In mechanical clocks, a part called the escapement mechanism controls this sound.

The familiar tick-tock of wall clocks originates from the escapement mechanism, which controls gear movement in precise steps. While our brains perceive two distinct sounds, clocks actually produce ...