General Science Concepts Flashcards

A soldier wearing a thick fleece jacket in a cold environment stays warm primarily because the jacket's material is effective at which of the following?

Answer: Trapping a layer of air, which is a poor conductor of heat

Insulating clothing, like fleece or wool, works by trapping many small pockets of air within its fibers. Air is a poor conductor of heat, which means it significantly slows down the rate at which body heat is lost to the colder surrounding environment. The jacket itself does not generate heat.

A maintenance crew notices that a steel tool left outdoors has developed a reddish-brown coating of rust. This rust formation is a classic example of what type of chemical reaction?

Answer: Oxidation

Rusting is the common term for the corrosion of iron and its alloys, such as steel. It is an oxidation reaction where iron reacts with oxygen and water in the air to form iron oxide.

An aircraft carrier's catapult system launches a jet, causing it to accelerate from a standstill to over 150 mph in just a few seconds. This rapid change in velocity from a large applied force is a direct application of which principle?

Answer: Newton's Second Law (Force = mass × acceleration)

Newton's Second Law of Motion states that the acceleration of an object is directly proportional to the net force applied and inversely proportional to its mass (F=ma). The catapult applies a tremendous force to the jet's mass, resulting in very high acceleration.

During a field exercise on a cool, clear night, soldiers notice that the outside of their canteens are wet with dew by morning. This formation of liquid water from vapor in the air is an example of what process?

Answer: Condensation

Condensation is the process where water vapor (a gas) in the air turns into liquid water. As the air cools during the night, its ability to hold water vapor decreases, causing the vapor to condense onto cool surfaces like the canteens.

On a remote mission, a team relies on local vegetation as a potential resource. The primary process by which green plants convert light energy from the sun into chemical energy (food) is known as:

Answer: Photosynthesis

Photosynthesis is the process used by plants, algae, and certain bacteria to harness energy from sunlight and turn it into chemical energy in the form of glucose or other sugars.

A puddle of water on a hot runway slowly disappears over time without ever boiling. Which scientific process best describes this change from a liquid to a gas?

Answer: Evaporation

Evaporation is the process where a liquid turns into a gas at a temperature below its boiling point. The heat from the sun and runway provides energy to the water molecules, allowing them to escape into the air as water vapor.