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Dr. Christopher S. Baird

How can you cancel out the jolt of a quick start?

Category: Space      Published: February 14, 2013

Acceleration always creates inertial forces. When you slam on your car's gas pedal, the rapid acceleration throws you back into your seat. The force you feel pushing you back is called an "inertial force". Every time a frame of reference is accelerated, objects in that frame of reference experience an inertial force. The greater the acceleration, the greater the force. Fighter jets that accelerate at high rates contain pilots that have to be specially trained to handle the high inertial forces (known to them as "g"-force or pulling "g"s). If the acceleration is small enough, the inertial force my not be noticeable. But all practical vehicles have high enough accelerations for their inertial forces to be felt. The fact that acceleration always causes inertial forces is universal and fundamental. There is no way to use technology to cancel out inertial forces. In terms of entertainment, this means that every time a space ship in a show speeds up, the actors should be visibility pushed back into their chairs, or be knocked over if standing. Similarly, every time the ship slows down, the actors should lurch forwards. This particular principle of physics is easy to act out, cheap to implement, and adds more drama, not less. Shows that get this principle wrong do so simply out of incompetence.

Topics: acceleration, high gs, inertia, inertial dampers, jerk, jolt, mass, space movie