TeXes Science Practice Test

What physical principle explains why your weight would decrease in a thicker atmosphere?

1. Newton's Third Law

2. Archimedes' Principle

3. Law of Conservation of Energy

4. Bernoulli's Principle

The correct answer is: Archimedes' Principle

The reason why your weight would decrease in a thicker atmosphere relates to Archimedes' Principle. This principle states that the upward buoyant force experienced by an object submerged in a fluid is equal to the weight of the fluid that the object displaces. In a thicker atmosphere, there are more air molecules present, which increases the density of the air. When standing in such an atmosphere, a person displaces more air, creating a substantial buoyant force acting upward. This buoyant force effectively reduces the net downward force, or weight, that the person feels. Essentially, the thicker atmosphere provides greater support and flotation, leading to a decrease in the sensation of weight, even though the gravitational force acting on the mass of your body remains constant. Understanding the principles of buoyancy and atmospheric density can help in recognizing how variations in environmental conditions can affect perceived weight.