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Right option is (b) Brine

The explanation is: Brine is a high-concentration solution of salt (usually sodium chloride) in WATER. In different contexts, brine may refer to salt SOLUTIONS RANGING from about 3.5% (a typical concentration of seawater, on the LOWER end of solutions used for brining foods) up to about 26% (a typical saturated solution, depending on temperature).

The correct choice is (c) they PARTLY escape into atmosphere

The explanation: Non condensable are environmentally UNDESIRABLE because they partly escape into the atmosphere. Most are corrosive in the normal damp atmosphere of the PLANT and are NOXIOUS and toxic and hence major pollutants.

Right option is (b) Water

For explanation: In the open/Claude cycle, water is the WORKING fluid. The warm water surface water is caused to boil by lowering the pressure, without supplying any additional HEAT. The LOW pressure steam produced then, DRIVE’s the TURBINE and the exhaust steam is condensed by the deep colder water is discarded.

Correct option is (b) 340

Easy explanation: There are about 340 known geothermal areas in India, each represented by hot or warm SPRINGS. MANY more areas are being discovered and REPORTED, in the 12 well defined geothermal provinces.

Right option is (c) Re-injection

The best explanation: Re-injection could avoid discharging large quantities of heat into rivers, with consequent hazards to FISHERIES, and would ALSO avoid infecting rivers and stream with toxic SUBSTANCES emitted from the bores which would endanger DOWNSTREAM with toxic substances, water supplies and FARMING activities.

Right choice is (a) Chrome STEEL

For explanation I would say: In the turbine, steam nozzles and blades are SUBJECTED to DRY or high QUALITY steam is usually made of 11 to 13 percent chrome steel. The nozzles are usually designed with large throat areas o a wide pitch to minimize scaling.

Correct answer is (b) Dolphin type wave generator

For EXPLANATION I WOULD say: Dolphin type uses the float which has two MOTIONS. The first is a rolling MOTION about its own fulcrum with the connecting rod. Revolving movements are caused between the float and the connecting road. The other is nearly vertical or heaving motion about the connecting rod fulcrum.

Right ANSWER is (a) Non – conventional

The best EXPLANATION: Wave energy is free and non-conventional source of energy. Harnessing of energy by this METHOD is RELATIVELY pollution free and because they remove energy from the waves, leaves the WATER in a relatively placid state in their wakes.

The correct option is (a) Microseisms

The best I can explain: Oscillatory motion is highest at the surface and diminishes exponentially with DEPTH. However, fornear a REFLECTING coast, wave energy is ALSO present as pressure OSCILLATIONS at great depth, producing microseisms.

Correct OPTION is (b) TIDAL FLUCTUATION

To explain: The two pool tidal system is less dependent on tidal fluctuation but is more complex and involves more costly dam construction. An INLAND basin is enclosed by dam A and is divided into a HIGH pool and a low pool by dam B.

Right option is (b) Cooling towers

Easy explanation: A direct system is used at the geysers in which the turbine EXHAUST steam is condensed by direct CONTACT with cooling WATER. The resulting warm water is circulated through a mechanical DRAFT cooling TOWER and returned to the condenser.

Correct choice is (c) Damping fins

To EXPLAIN: Damping fins are used to reduce the motion of the FLOATS. The platform is stabilized within the water by four LARGE underwater floatation tanks so that it is SUPPORTED by the buoyancy forces. The floatation tank’s SURFACES are wider in appearance and are flat.

The correct answer is (b) South KOREA

To EXPLAIN: Sihwa LAKE Tidal Power Station is the world’s largest tidal power installation, with a TOTAL power OUTPUT capacity of 254 MW. When completed in 2011, it surpassed the 240 MW Rance Tidal Power Station which was the world’s largest for 45 years. It is operated by the Korea Water Resources Corporation.

The correct choice is (a) 2.4 X 10^6 MW

Best explanation: The TOTAL tidal power that is dissipated throughout the world is estimated at 2.4 X 10^6 MW of these some 10^6 MW are dissipated in SHALLOW seas and COASTAL areas and are not recoverable. Because of very high cost of dams and other STRUCTURES associated with tide energy conversion system, only a small amount of the rest can be satisfied by tidal energy.

The correct option is (b) GEO-Thermal energy

Easiest EXPLANATION: The process of producing energy by utilizing heat trapped inside the earth SURFACE is called Geo thermal energy. Energy present as heat in the earth’s crust. The more READILY accessible heat in the upper most (10 km) or so, of the crust constitutes a potentially useful and almost inexhaustible source of energy.

The correct ANSWER is (b) Kaplan turbine

To ELABORATE: The Kaplan turbine is a propeller TYPE reaction turbine that is usually immersed completely in the fluid it derives energy from. A Kaplan turbine is beneficial in that it is able to operate in lower PRESSURE SITUATIONS where Pelton or Francis turbines cannot.

Right answer is (b) density

To EXPLAIN I would say: Water density decreases with an increase in temperature. Thus, there will be no thermal convection currents between the warmer, LIGHTER water at the top and the deep cooler, heavier water. Thermal conduction heat transfer between them, ACROSS the large depths, is too low and thus MIXING is retarded, so the warm water stays at the top and cool water stays at the BOTTOM.

Right option is (b) Magma

For explanation I would say: Magma is a mixture of molten or semi-molten rock, volatiles and solid that is found beneath the surface of the Earth, and is expected to exist on other terrestrial planets and some natural SATELLITES. Besides molten rock, magma may ALSO CONTAIN suspended crystals, DISSOLVED gas and sometimes gas bubbles.

Correct choice is (a) Barjot

Explanation: The CLOSED cycle approach was first proposed by Bajrot in 1926, but the most recent design was by Anderson in 1960s. The closed cycle is sometimes REFERRED to as Anderson cycle. The Anderson cycle chose PROPANE as WORKING fluid.

The correct ANSWER is (c) Closed cycle

Easiest EXPLANATION: Anderson cycle is also called as closed cycle. Closed cycle utilizes the oceans warm SURFACE and cool deep waters heat source and sink RESPECTIVELY, but requires a separate working fluid that receives and rejects heat to the source and sink via heat exchanges.

Correct choice is (a) Carnot cycle

The best EXPLANATION: The MAXIMUM possible efficiency of a heat engine operating between two temperature limits cannot EXCEED that of a Carnot cycle operating between the same temperature limits. The Carnot efficiency is given by

ηc = (T1-T2)/T1.

Correct answer is (b) False

To explain I would say: The tides are rhythmic but not constant. They do not occur on a regular DAILY SCHEDULE. Their occurrence is DUE to balance of FORCES, mainly the gravitational force of the moon but ALSO that of the sun, both acting together with that of earth to balance the centrifugal force on the water to the earth’s rotation.

Correct option is (b) Ocean thermal energy conversion

To explain: Ocean thermal energy conversion (OTEC) uses the temperature difference between cooler deep and warmer shallow or surface SEA WATER to RUN a heat engine and produce useful work, usually in the form of electricity. OTEC can OPERATE with a very high capacity factor and so can operate in base mode.

Correct choice is (b) 2

The BEST explanation: In the SIMPLE single pool system two high peaks, short DURATION power outputs occur every tidal period. Such peaks require large turbine-generators that remain IDLE much of the time. The power peaks also occur at different times every day (50 min later each successive day), at times of high and low tides.

Right option is (b) Flashed STEAM system

The best I can explain: Flashed steam system is USED for water in the higher temperature RANGE. Flash steam is low-pressure steam created when hot water is released from a HIGH pressure to a lower pressure within a steam system.

Correct option is (b) 15%

Explanation: GEOTHERMAL power plants have lower efficiency RELATIVE to other thermal power plants, such as coal, natural gas, oil, and NUCLEAR power STATIONS. It is commonly assumed that only 15% of the ENERGY from the produced geothermal fluid can be converted to electricity.

Correct option is (b) Sluice gates

The best explanation: A sluice is a water CHANNEL CONTROLLED at its head by a gate. A sluice gate is traditionally a wood or metal barrier SLIDING in grooves that are set in the sides of the waterway. Sluice gates commonly control water levels and flow rates in RIVERS and CANALS.

Correct option is (B) It is available only in ocean

Explanation: The major DISADVANTAGE of wave energy is that the energy is available on the ocean. The extraction equipment must be operated in a marine environment with all that IMPLIES in terms of MAINTENANCE, construction COST, life time and reliability.

The correct answer is (a) By wind SPEED

For explanation: Wave height is DETERMINED by wind speed, the duration of TIME the wind has been blowing, fetch and by the depth and topography of the seafloor. A given wind speed has a matching practical limit over which time or distance will not PRODUCE larger waves.

The correct answer is (b) SOLAR energy

The explanation: Like the wind and OTEC, ocean and sea waves are caused indirectly by solar energy. Waves are caused by the wind, which in TURN is caused by the uneven solar HEATING and SUBSEQUENT cooling of the earth’s crust and the rotation of the earth.

Right choice is (d) TIDAL Current

To elaborate: Movement of WATER generated by or associated with the change in mean sea level is called tidal currents. Tidal currents occur in conjunction with the rise and FALL of the tide. The vertical motion of the tides near the shore causes the water to move horizontally, CREATING currents.

The correct choice is (a) 7 meters

Best explanation: The tidal range MUST be at least 7 meters (23 FEET) for a barrage to be feasible. There are only three commercial-size barrage SYSTEMS operating: one in FRANCE (240 MW), one in Nova Scotia (20MW), and one in Russia (500 kW).

Right option is (B) Dredging

The explanation is: Dredging is an excavation activity usually carried out underwater, in SHALLOW seas or freshwater areas with the purpose of gathering up bottom sediments and widening. This technique is often used to KEEP waterways NAVIGABLE and creates an anti sludge PATHWAY.

The correct choice is (a) RESULTING work is reduced

For explanation: Because the AVERAGE head h is lower and work and power are PROPORTIONAL to h^2, turbine generators are much smaller and operate over a much longer period. The resulting total work is reduced.

Correct choice is (a) 2

The best explanation: There are TWO possible arrangements for hybrid plants. These are (1) geothermal preheat SUITABLE for low temperature liquid DOMINATED systems, and (2) fossil superheat, suitable for vapor dominated and high temperature liquid dominated systems.

The correct choice is (d) 3000 – 280,000 ppm

For EXPLANATION: The water comes with various degrees of salinity, ranging from 3000 to 280,000 ppm of dissolved solids, and at various temperatures. There are, therefore, various SYSTEMS for CONVERTING liquid dominated system into useful WORK that depend upon these variables.

Right choice is (a) d’Arsonval

To elaborate: The concept of OCEAN temperature energy conversion is based on the utilization of temperature DIFFERENCE in a heat engine to generate POWER. It was first recognized by Frenchman d’Arsonval in the YEAR 1881.

Right answer is (c) Tidal RANGE

To explain I would say: The tidal range is the VERTICAL difference between the high tide and the succeeding low tide. Tides are the rise and fall of sea levels caused by the COMBINED EFFECTS of the GRAVITATIONAL forces exerted by the Moon and the Sun and the rotation of the Earth.

Correct option is (c) Condenser ejectors

The explanation: The non condensable gas content VARIES from 0.2 – 0.4 percent depending upon the particular well and its AGE. The non condensable themselves are MOSTLY CO2 plus varying amount of methane CH4, hydrogen H2, nitrogen, ammonia and hydrogen SULFIDE. Besides finding way with the fluid into the plant equipment the non condensable partly escape to atmosphere via condenser ejectors.

Correct answer is (a) Through fissures

Easy explanation: HOT water or steam often escapes through fissures in the rock, thus forming hot springs, geysers fumaroles ETC. in ORDER to utilize the hydrothermal ENERGY, wells are drilled either to intercept a fissure or more commonly into the formation containing the water.

The correct answer is (a) 200^oC

To elaborate: The HEAT is apparent from the INCREASE in temperature of the earth with increasing DEPTH below the surface. Although higher and lower temperature occurs, the average temperature at depth of 10 km is about 200^oC.

Correct answer is (a) 2

For explanation: There are TWO kinds of GEO thermal steams, the one that originates from the magma is called magmatic steam and that from GROUND water heated by magma is called meteoritic steam. The LATTER is the LARGEST source of geothermal steam.