UPSC Prelims 2020 · GS Paper I
Question 88: Economy and Social Development
With reference to solar water pumps, consider the following statements :
- 1.Solar power can be used for running surface pumps and not for submersible pumps.
- 2.Solar power can be used for running centrifugal pumps and not the ones with piston.
Which of the statements given above is/are correct ?
AnswerUPSC’s answer is (d).
Solar power can run both surface and submersible pumps, so statement 1 is wrong. Solar pumping systems use centrifugal pumps as well as positive displacement pumps with pistons, so statement 2 is wrong too. The choice of pump depends on the water source and the head, not on the power source.
- 1. Solar power can run submersible pumps as well.
- 2. Solar power can run piston (positive displacement) pumps as well.
How you could have got this
- If you were sure statement 1 is not correct, (a) and (c) go: each of them includes 1.
What you needed to know: Solar power can run submersible pumps as well.
- Then, if you were sure statement 2 is not correct, (b) goes: it includes 2.
What you needed to know: Solar power can run piston (positive displacement) pumps as well.
Only (d) is left. This one needs every statement.
Which options go is worked out from UPSC’s key and the options, not by a model.
Why each option is right or wrong
- (a) Wrong: solar can power submersible pumps too.
- (b) Wrong: solar can power piston pumps too.
- (c) Wrong: both statements are false.
- (d) Right: neither statement is correct.
Answer: UPSC’s key. Explanation: written by UPSC Grade, not by UPSC.
Source: UPSC, Civil Services (Preliminary) Examination 2020, General Studies Paper I, Series A. The paper on upsc.gov.in.