There is a balanced force acting on you gravity pulling down, your seat pushing up. Right now, gravity is pulling you down in your seat, but Newton’s Third Law says your seat is pushing up against you with equal force.
This segment comprises The Law of Inertia: Newton’s First Law Force Equals Mass Times Acceleration: Newton’s Second Law and The Law of Action and Reaction: Newton’s Third Law. For every force acting on an object, there is an equal force acting in the opposite direction. A formula is shown, and the calculation is made to reveal the instructor’s mass in slugs. The instructor then proceeds to step on a scale. For example, the instructor explains how viewers can calculate a person’s mass by dividing the weight of that person by the acceleration due to gravity. Formulas are presented onscreen along with the calculations discussed in the segment.
Viewers watch an instructor at NASA’s National Test Pilot School as he describes and then demonstrates why seatbelts are an important force on pilots what it means to pull 2, 4 and even 6 g in a jet and how the thrust of a jet engine causes an aircraft to move forward. This NASA video segment explores how Newton’s Laws of Motion apply to the development and operation of airplanes.
