Everyday Science

Tocopherol (Vitamin E) is a fat-soluble vitamin, whereas Pyridoxine (Vitamin B6), Pantothenic acid (Vitamin B5), and Niacin (Vitamin B3) are all water-soluble vitamins. Therefore, Tocopherol is the correct answer as it is not water soluble.

A loudspeaker converts electrical energy into sound energy by using electrical signals to move the speaker cone, producing sound waves.

The average distance between the Earth and the Moon is approximately 384,400 kilometers, which corresponds to option D. This is a well-established scientific fact.

One Quintal is a unit of mass equal to 100 kilograms, which is why option D is correct.

In space, due to microgravity, the body experiences weightlessness and effectively loses weight as there is no significant gravitational pull acting on it. This is why astronauts appear weightless while in orbit.

The density of air at standard temperature and pressure (around 15°C and 1 atm) is approximately 1.225 kg/m³, making option C the correct choice.

Glass is primarily made from silica, which is found in sand, combined with other silicates to form the glass mixture. This makes option C the correct answer.

The sun appears oval near the horizon because its light rays are refracted differently at various angles as they pass through Earth's atmosphere, causing the vertical dimension to be compressed more than the horizontal, resulting in an oval shape.

Apollo XI was the spacecraft that enabled humans to land on the Moon for the first time, with Neil Armstrong stepping onto the lunar surface in 1969. The other options were earlier Soviet spacecraft involved in space exploration but did not land humans on the Moon.

Normal rain is slightly acidic because carbon dioxide from the atmosphere dissolves in rainwater and reacts with water to form a weak acid called carbonic acid, which lowers the pH slightly below neutral.