CAPF (AC) 2013 (Paper-1) (Question 1-50)

The primary component of natural gas is methane (CH₄) the shortest and lightest hydrocarbon molecule. It also contains heavier gaseous hydrocarbons such as ethane (C₂H₆) , propane (C₃H₈) and butane (C₄H₁₀) as well as other sulphur containing gases, in varying amounts.

It is a hydrocarbon mixture made up of mainly methane which is gaseous under atmospheric conditions. It is a fossil fuel. It is a non-renewable hydrocarbon used as a source of energy for heating, cooking, and electricity generation. It is a mixture of gases that are rich in hydrocarbons.

Polymorphism is the phenomenon of a substance different crystal structures. Graphite is transformed into diamond under high pressure (around 55,000 atmospheres) and high temperature (about 1400 degrees C).

Diamond is a polymorph of the element carbon. It is the ultimate gemstone, having few weaknesses and much strength. It is a good electrical insulator. Graphite is another polymorph. It is a good conductor of electricity and a very good lubricant.

Plant growth, vigour and yield are dependent upon the availability of many essential element nutrients. These elements include three primary soil micro-nutrients such as nitrogen, phosphorous, potassium.;

Micronutrients are very abundant in soil but plants normally absorb only a little amount of them, giving them the name "trace elements"”. Boron (B), Copper (Cu), Iron (Fe), Manganese (Mn), Zinc (Zn), Molybdenum (Mo), and Nickel (Ni) are the essential micronutrients that are required in smaller amounts but crucial for plant growth and development.

Besides providing essentiality in fruits and seeds formation, they are helpful in performing various metabolic processes, nutritional management, reproductive growth, chlorophyll synthesis, and other key plant activities.

Among all the essential micronutrients, two particular elements, zinc (Zn) and boron (B) are deficit in acidic soils and zinc (Zn) and iron (Fe) are insufficient in semi-arid soils, which have become a rising problem in a variety of cropping systems thereby, raising alarms for the future.

The Baily's beads effect, or diamond ring effect, is a feature of total and annular solar eclipses. As the Moon covers the Sur. during a solar eclipse, the topography of the lunar limb allows beads of sunlight. Baily's beads, the arc of bright spots visible during total and yearly eclipses of the Sun.

Due to the craters, mountains and valleys on the moon's surface, a unique effect occurs during a total solar eclipse. When rays, or beads, of sunlight shine past the edge of the moon in certain plays during an eclipse, and the rest of the moon's circumference is dark, those places are known as Baily's beads.

Turing machines, first described by Alan Turing, are simple abstract computational devices intended to help investigate the extent and limitations of what can be computed. Turing's 'automatic machines', as he termed them in 1936, were specifically designed for the computing of real numbers.

They were first named 'Turing machines' by Alonzo Church in a review of Turing's Paper (Church 1937). Turing machines are regarded as one of the foundational models of computability and (theoretical) computer science.

Leaves of lotus and water lily are not easily wet because leaves of each of these plants are covered with an array of tiny bupbs. This uneven surface is itself covered with waxy hydrophoci crystals. The two-tier roughness on leaf's surface minimises the contact between the solid surface and waterdrops. You trap air below your drop so drop sits on the patchwork of solid.

Arsenic is naturally occurring in groundwater in both the arsenite and arsenate forms. Found in rocks, soil, water, air and biota, arsenic's natural concentrations in soil typically range from 0.1 to 40 mg/kg. Technological options to combat arsenic menace, in groundwater, to ensure supply of arsenic free water, in the affected areas, can be one of the followings or a combination of all:

(i) In-situ remediation of arsenic from aquifer system,

(ii) Ex-situ remediation of arsenic from tapped groundwater by arsenic removal technologies,

(iii) Use of surface water source as an alternative to the contaminated groundwater source,

(iv) Tapping alternate safe aquifers for supply of arsenic free groundwater.

The transformer is used to convert the voltage from low to high or vice versa relying upon the efficiency for power transfer and use and since it is an application of the changing due to change in magnetic flux which is developed by changing current it can be only applied to the air conditioner.

Transformers are applied for widely varying purposes, e.g., to reduce the voltage of conventional power circuits to operate low-voltage devices, such as doorbells and toy electric trains, and to raise the voltage from electric generators so that electric power can be transmitted over long distances,

The filament of an electric bulb is generally made of tungsten because the melting point of tungsten is very high. This metal bond with extremely high bond energy. Out of all the metal elements in the periodic table, the element of tungsten is the element with the highest melting point, and its melting point reaches 3422 °C. It can reach a high melting point so the greatest tensile strength of any metal, lowest vapour pressure and also the highest melting point.

An electric meter is an analog machine that is used to measure the electrical energy usage of a home, building, or another electrically powered device. Analogue meters are the basic and time-tested meters that are used for monitoring the electricity usage.

These meters have multiple spinning dials which are read to find out the accurate amount of energy consumed. They are applied to measure accurate billing to customers.