Tag: science & technology

A hectare is a metric unit of area equal to 10,000 square meters. In imperial units, 1 hectare ≈ 2.47 acres. The conversion commonly used is 1 hectare ≈ 2.5 acres for rough calculations. This makes 2.5 acres the closest correct answer. Hectares are widely used in land measurement internationally, especially in agriculture and real estate.

Absolute zero is the lowest possible temperature, defined as 0 Kelvin (or -273.15°C and -459.67°F). At absolute zero, all thermal motion ceases theoretically. Kelvin is the absolute temperature scale where 0 K represents absolute zero.

The ozone layer is located in the stratosphere, approximately 10-50 kilometers above Earth's surface. It absorbs harmful ultraviolet radiation from the sun. The troposphere is the lowest layer, thermosphere is higher, and lithosphere is Earth's crust.

JCL (Job Control Language) is indeed a scripting language used on IBM mainframe operating systems (like z/OS) to instruct the system on how to run batch jobs. It defines the job's steps, resources needed, and execution parameters.

The mandible (lower jaw bone) is the only movable bone in the human skull. All other cranial bones are fixed through sutures (fibrous joints), while the mandible connects to the skull via the temporomandibular joint, allowing movement for chewing and speaking.

Sound waves are longitudinal waves where particles vibrate parallel to the direction of wave propagation. Light waves are transverse electromagnetic waves where oscillations occur perpendicular to the direction of propagation.

Sound travels fastest in solids because particles are closely packed, allowing faster transmission of vibrations. Speed of sound decreases from solids (~6000 m/s in steel) to liquids (~1500 m/s in water) to gases (~343 m/s in air). Sound cannot travel in vacuum.

Protium is the hydrogen isotope with no neutrons - it consists of just one proton and one electron (¹H). Deuterium has 1 neutron, and Tritium has 2 neutrons. The option claiming 'all isotopes contain atleast 1 neutron' is false.

Air has a refractive index very close to 1, typically 1.0003 at standard temperature and pressure. This means light travels only slightly slower in air than in a vacuum. The value 1.33 is for water, 1.6 for some glass, and 2.33 for some diamond-like materials.

Vitamin B1 is chemically known as thiamine. Beriberi is indeed caused by thiamine (vitamin B1) deficiency. L-ascorbic acid is vitamin C, cobalamin is vitamin B12. This is a basic biochemistry/nutrition question testing vitamin names and their deficiency diseases.