Question

On a flight to Europe, you notice that the packages of peanuts are puffed up. Why? 1. The jet is over-pressurized at high altitudes, thus causing the gas inside the packages to expand. 2. The air in the jet is approximately ten times hotter than on the ground, thus increasing the temperature of the gas in the packages. 3. The peanuts have greater velocities at high altitudes, thus causing the peanuts to exert more force on the packaging. 4. The packages are puffed up on the ground due to overinflation with helium. This type of packaging provides extra buoyancy for aircrafts. 5. They were packaged at a higher pressure on the ground, thus causing the gas inside the packages to expand in the sky where the jet is at a lower pressure.

Answer 1

The correct answer is;

5. They were packaged at a higher pressure on the ground, thus causing the gas inside the packages to expand in the sky where the jet is at a lower pressure.

Step-by-step explanation:

According to Boyle's law, the pressure of a given mass of gas is inversely proportional to it volume at constant temperature

P₁·V₁ = P₂·V₂

At the factories, the peanuts are packaged at atmospheric conditions whereby P₁ = 1 atm, however, the pressure of the air in the atmosphere decreases with altitude as such the pressure in the airplane jet is about a fraction of hat on the ground by about a factor of 0.7.

Therefore P₂ = 0.7 atm and we have

V₂ = P₁·V₁/P₂ = 1 atm×V₁/0.7 atm = 1.43·V₁

The volume increases at high altitudes