Tag: science & technology

Air resistance is the force that opposes the motion of an object through the air. It is caused by air particles colliding with the moving object, slowing it down. This is why objects like parachutes experience drag when falling through air.

The mean free path is the average distance a particle (such as a molecule or atom) travels between successive collisions with other particles. This concept is important in the kinetic theory of gases and helps explain properties like viscosity and thermal conductivity.

The Sun is the star at the center of our solar system. All planets, including Earth, orbit around the Sun. The Moon orbits Earth, while Mars is a planet in the solar system.

Speleology is the scientific study of caves and cave systems. A speleologist studies caves, their formation, ecology, and history. Mineral deposits would be studied by mineralogists, trees by botanists/dendrologists, and mountains by geomorphologists or mountaineers.

Rust (iron oxide) is formed when iron combines with oxygen in the presence of moisture. This is a chemical reaction called oxidation. Sugar (carbon, hydrogen, oxygen), salt (sodium, chlorine), and chlorophyll (carbon, hydrogen, oxygen, nitrogen, magnesium) are compounds not formed from iron and oxygen.

The correct biological name for humans is Homo sapiens. Option A has a typo ('sapient' instead of 'sapiens'). The genus name Homo is always capitalized, and the species name sapiens is lowercase in scientific writing.

The femur, or thigh bone, is the longest and strongest bone in the human body. It extends from the hip to the knee and can withstand significant force due to its role in supporting body weight and movement.

The smallest bone in the human body is the stapes (stirrup bone) in the middle ear. It's approximately 3mm long and transmits sound vibrations from the incus to the inner ear. The inner ear contains the three smallest bones: malleus, incus, and stapes.

The pituitary gland is called the 'master gland' because it controls other endocrine glands by secreting hormones that regulate their function. It produces hormones like TSH (thyroid), ACTH (adrenal), and FSH/LH (reproductive) that stimulate other glands. The thymus produces T-cells, the pancreas regulates blood sugar, and ovaries produce eggs - none regulate the entire endocrine system.