Everyday Science

Fiber helps in preventing constipation by adding bulk to the stool and facilitating its passage through the digestive tract, thus promoting regular bowel movements.

Optical fibers are primarily used in communication systems because they can transmit data as light signals over long distances with minimal loss and high bandwidth.

Over-cooking food reduces its nutritional value by destroying heat-sensitive vitamins and nutrients, making option B the most accurate reason to avoid over-cooking. While over-cooking can affect digestibility and potentially produce harmful substances, the primary concern is nutrient loss.

Stone is a solid because it has a fixed shape and volume, unlike water which is a liquid. Therefore, option B is correct.

The red color of tomatoes is due to lycopene, a red carotenoid pigment. Anthocyanins and xanthophylls are pigments responsible for other colors in plants but not the red color of tomatoes.

The Moon is the Earth's only natural satellite, meaning it formed naturally and orbits the Earth without human intervention. Artificial satellites are man-made objects placed in orbit, which the Moon is not.

Hydrogen is the lightest element and substance among the options listed, having the lowest atomic mass and density.

Coal is a fossil fuel and is not renewable because it takes millions of years to form and cannot be replenished on a human timescale. Wind energy, solar energy, and hydroelectric power are all renewable sources as they rely on natural processes that are continuously replenished.

Liquids that evaporate quickly are called volatile liquids because they have high vapor pressure and low boiling points, causing them to vaporize easily at room temperature.

Balloons are commonly filled with helium because it is lighter than air, allowing the balloons to float. Nitrogen, oxygen, and argon are heavier or do not provide buoyancy like helium does.