Everyday Science

Smoke consists of tiny solid particles suspended in a gas (air), making it a solid in gas mixture. Therefore, option C is correct.

The ozone layer is primarily composed of ozone molecules, which consist of three oxygen atoms (O3). This layer protects the Earth from harmful ultraviolet radiation.

LPG (Liquefied Petroleum Gas) mainly consists of propane (C3H8) and butane (C4H10) in varying proportions. It may also contain smaller amounts of ethane and other light hydrocarbons, but methane is not a significant component of LPG. Hexane and nonane are not typical constituents of LPG. Therefore, the correct answer is C: Methane, Butane & Propane, although methane is usually minimal or absent in LPG. The question option C is the closest correct choice, and the explanation is updated to clarify that methane is generally minimal or absent in LPG, with propane and butane being the main components.

A nanometer (nm) is defined as one billionth of a meter, which is 10 to the power of -9 meters. Therefore, 1 nanometer equals 10^-9 meters.

The solar wind, a stream of charged particles emitted by the Sun, creates a vast bubble in the interstellar medium known as the heliosphere. This bubble protects the solar system from cosmic radiation.

Amino acids are the building blocks of proteins and are produced when proteins are digested by enzymes in the body. Carbohydrates, fats, and vitamins do not break down into amino acids.

Crookes glass is specially designed to block ultraviolet rays, making it effective in cutting UV radiation. The other types of glass listed do not have this specific property.

CNG stands for Compressed Natural Gas, which is a fuel gas consisting primarily of methane compressed to less than 1% of the volume it occupies at standard atmospheric pressure.

Vitamin D deficiency leads to rickets, a condition characterized by weak or soft bones in children due to impaired calcium absorption. Night blindness is caused by vitamin A deficiency, scurvy by vitamin C deficiency, and hair fall is not directly linked to vitamin D deficiency.

Burning fossil fuels releases carbon dioxide and other greenhouse gases into the atmosphere, which increases the greenhouse effect and contributes to global warming.

The stomach primarily functions as a storage organ for food before it is digested. It temporarily holds the ingested food, mixing it with gastric juices for digestion.

The density of water at standard temperature and pressure is approximately 1 gram per cubic centimeter (1 g/cm³), which is a well-established scientific fact.

White light splits into seven distinct colors when passed through a prism, commonly known as the colors of the visible spectrum: red, orange, yellow, green, blue, indigo, and violet.

Aluminium, gold, and graphite are all conductors of electricity. Aluminium and gold are metals known for their excellent electrical conductivity, while graphite, a form of carbon, also conducts electricity due to its structure. Therefore, the correct answer is D, as all listed options are conductors.

BTU (British Thermal Unit) is a unit of energy commonly used to measure heat. It represents the amount of heat required to raise the temperature of one pound of water by one degree Fahrenheit.

Severe deficiency of Vitamin D leads to rickets, a condition characterized by softening and weakening of bones in children. Scurvy is caused by Vitamin C deficiency, and night blindness is due to Vitamin A deficiency.

Atmospheric pressure decreases with increasing altitude because the density of air molecules becomes lower as you move higher away from Earth's surface.

Salt is commonly spread on icy roads during winter to lower the freezing point of water, causing ice to melt and making roads safer to drive on.

A battery converts chemical energy directly into electrical energy through electrochemical reactions, making it the correct answer. Motors convert electrical energy into mechanical energy, generators convert mechanical energy into electrical energy, and moving-coil meters measure current or voltage.

A monoatomic molecule consists of a single atom. Helium is a noble gas that exists naturally as single atoms, making it monoatomic. Ozone, hydrogen, and nitrogen are diatomic or triatomic molecules.

The average human breathes in about 15,000 to 20,000 liters of air per day, considering an average respiratory rate and tidal volume. This makes option C the most accurate choice.

The first shell (K shell) of an atom can hold a maximum of 2 electrons because it contains only one s orbital, which can accommodate 2 electrons with opposite spins.

A pyrometer is an instrument specifically designed to measure very high temperatures, often in industrial settings, whereas a pyroscope is not a standard term for temperature measurement. Seismograph measures earthquakes, and xylometer is not related to temperature measurement.

Hydrogen is the most abundant element in the universe, making up about 75% of its elemental mass. This is because hydrogen is the simplest and lightest element, formed in vast quantities after the Big Bang.

Long-sightedness (hypermetropia) occurs when the eye focuses images behind the retina. It is corrected using a convex lens, which converges light rays to focus correctly on the retina.