An engineer claims that solar cells for the generation of

Question

An engineer claims that solar cells for the generation of electrical power can never meet our high demand for electrical energy. He points out that such cells are made largely of silicon, and that silicon is extracted and refined by the use of electrical energy. He says that the amount of energy required to produce the silicon in a solar cell is greater than the energy that cell will produce during its useful working life. 

The engineer's conclusion seems to depend on which of the following assumptions?

A) We will not continue to produce large amounts of electrical energy by burning fossil fuels.

B) Our overall need for electrical energy cannot be reduced.

C) We will not find more efficient ways of extracting and refining silicon.

D) Electrical energy, since it does not decay, can be recycled indefinitely.

E) It will soon become economically feasible to harness solar energy by other means, by heating water and using the water to power 'minimum gradient' engines.

please explain

Raghavender · Answer

Correct C. 

It is the basic assumption that in the future also, for mass production of solar cells, the same economics hold good. That is, we will not find more efficient ways of extracting and refining silicon.

shahnandan · Answer

ps_dahiya · Answer

Should be C.

Negate C and argument falls apart.

buzzgaurav · Answer

Easy C.
  the amount of energy required to produce the silicon in a solar cell is greater than the energy that cell will produce during its useful working life 
For this to be true we have to assume that
 We will not find more efficient ways of extracting and refining silicon

jaynayak · Answer

Clear winner C.

The engineer obviously assumes that there is no better way now nerither there will be in the future, hence comes to an extreme conclusion that solar cells will never be able to fulfill our power needs.

Gauss · Answer

C is the answear rely on the assumption that other ways of getting energy will not be found,.... E seems to go against the conclusion because describe alternative ways and A, B and D are out of scope

parvathaneni · Answer

The answer is c

hemamalinidr · Answer

It is C.

Futuristic · Answer

C for me

u2lover · Answer

was this too easy? :lol:

should I only post "the killers"? :roll:

OA is C indeed

Raghavender · Answer

Not tht we r too intelligent, but jus want more tough ones to sharpen our blunt minds... Please post the killers...

An engineer claims that solar cells for the generation of

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