Hear it before you see it: The Doppler Effect

One way to give the effect of a moving object is to use sound. A moving object making a particular sound, such as an ambulance with a blaring siren, can seem to be making sounds with two different pitches. This is because of the way sound waves work. As a moving object approaches making sounds, […]

Real-Life Rocket

The 1995 film Apollo 13 is a historically-accurate recounting of the problems encountered by astronauts and engineers during the 1970 USA space mission of the same name. Although I didn’t see the launch of the Apollo 13 on TV, I did watch NASA’s live broadcast of the 1969 launch of the Apollo 11 (along with millions of other Americans […]

Speed, velocity, and acceleration

You are probably familiar with the terms speed, velocity, and acceleration in everyday language, and perhaps you have even used them interchangeably. In physics, these terms have precise definitions and are expressed in a certain way. Speed Speed is how fast something is going, regardless of its direction. It is expressed as distance per time. Common […]