Tag: science & technology

Option B (Sun) is correct. The Sun is the principal component of our solar system, containing approximately 99.86% of the solar system's total mass. All planets, asteroids, and comets orbit around it. Option C (Star) is technically true but less precise than Option B.

Option D is correct. The Sun appears white from space and its peak emission is in the green-blue portion of the visible spectrum. It appears yellow/orange from Earth's surface due to atmospheric scattering. Options A, B, and C are incorrect.

Option D is correct. The Latin word for Earth is 'Terra' (genitive 'Terrae'), which is the origin of words like 'terrestrial', 'terrain', and 'extraterrestrial'. Options A, B, and C are incorrect.

Option C is correct. The Jovian planets (gas giants) are Jupiter, Saturn, Uranus, and Neptune. Option A incorrectly includes Earth (a terrestrial planet), Option B incorrectly includes Pluto (a dwarf planet), and Option D incorrectly includes Earth.

The Sun is the closest star to Earth, approximately 93 million miles away. The Moon is Earth's natural satellite, not a star. The Sun is a G-type main-sequence star that provides light and heat to our planet.

Earth's escape velocity is approximately 25000 miles per hour (about 11.2 km/s). This is the minimum speed needed for an object to break free from Earth's gravitational pull without further propulsion. At this speed, an object can overcome Earth's gravity and escape into space, which is why spacecraft need to achieve this velocity for orbital missions or interplanetary travel.

Octopuses have three hearts - two branchial hearts that pump blood through the gills, and one systemic heart that pumps blood to the rest of the body. This unique cardiovascular system supports their active predatory lifestyle and helps maintain oxygenation in their complex circulatory system. When an octopus swims, the systemic heart actually stops beating, which is why they prefer crawling over swimming.

Heavy water uses deuterium (D), a heavy isotope of hydrogen, instead of regular hydrogen. The formula is D2O. H2O is regular water, H2O2 is hydrogen peroxide, and T2O uses tritium.

The Bhopal gas tragedy was caused by methyl isocyanate (MIC) gas leak from a pesticide plant. 'Methyl isocyanite' and 'Methyl isocynide' are incorrect spellings.