WBCS Prelims 2017 General Science Question and Solution

GENERAL SCIENCE QUESTION AND SOLUTION(QUIZ) - WBCS PRELIMS 2017

   In West Bengal Civil Service (WBCS) Preliminary Examination 2017, total 25 questions was asked from General Science.

1. The material used for safety from nuclear radiation is

[A]  Copper  

[B]  Platinum 

[C]  Iron  

[D] Lead

Correct Answer

Correct Answer: [D] Lead

2. The electric appliances in a house are connected

[A]  In series 

[B] In  parallel 

[C]  Either in series or in parallel

[D] Both in series and in parallel

Correct Answer

Correct Answer: [B] In  parallel 

3. The immersed portion of a piece of pure ice floating in water is

[A]  8/9th of its volume       

[B]  9/10th of its volume

[C]  10/11th of its volume

[D] 11/12th of its volume

Correct Answer

Correct Answer: [D] 11/12th of its volume

4. ‘Red’ is used as a danger signal because

[A]  Blood is red

[B]  Red light is scattered least by the air molecules

[C]  Red colour is easily available

[D] Red colour is soothing for eye

Correct Answer

Correct Answer: [B]  Red light is scattered least by the air molecules

5. A shaving brush is dipped in water. When taken out the hairs of the brush are seen to be drawn together due to

[A]  Surface tension of water

[B]  Viscosity of water

[C]  Elasticity of the hairs of the brush

[D] Temperature difference between air and water

Correct Answer

Correct Answer: [A]  Surface tension of water

6. A body is acted upon by two unequal forces in opposite directions, but not in one line. The effect is that the body will have

[A]  Only rotational motion

[B]  Only translational motion

[C]  Neither the rotational nor the translational motion

[D] Rotational as well as translational motion

Correct Answer

Correct Answer: [D] Rotational as well as translational motion

7. ‘RADAR’ stands for

[A]  Radio Detection and Ranging

[B]  Ready Advanced Appliance for Ranging

[C]  Range Detection Appliance for Airplane Ranging

[D] Ready Advanced Airplane Ranging 

Correct Answer

Correct Answer: [A]  Radio Detection and Ranging

8. A reaction is spontaneous when

[A]  ΔG = -ve        

[B]  ΔH = -ve        

[C]  ΔS = +ve        

[D] ΔS = -ve

Correct Answer

Correct Answer: [A]  ΔG = -ve        

9. Geometry of SF₄ is

[A]  Square planar        

[B]  Tetrahedral

[C]  Octahedral

[D] See-saw

Correct Answer

Correct Answer: [D] See-saw

10. The strongest electropositive element is

[A]  Cs

[B]  Li

[C]  Mg

[D] K

Correct Answer

Correct Answer: [A]  Cs

11. Conversion of CH₃C = CH to CH₃CH = CH₂ needs

[A]  Lindlar catalyst         

[B]  H₂Pd

[C]  NaBH₄  

[D] LiAlH₄

Correct Answer

Correct Answer: [A]  Lindlar catalyst         

12. Conversion of RBr to RMgBr requires

[A]  Mg / dry ether / N₂ -atmosphere

[B]  Mg / moist ether / N2 -atmosphere

[C]  Mg / ethanol / N2 -atmosphere

[D] Mg / dry ether / O2 -atmosphere

Correct Answer

Correct Answer: [A]  Mg / dry ether / N2 -atmosphere

13. The fastest SN¹ reaction is of the followings:

[A]  MeO – CH₂-Cl        

[B]  Me-CH₂-Cl

[B]  Me-C-CH₂-Cl       

[D] Ph-CH₂-CH₂-Cl

Correct Answer

Correct Answer: [A]  MeO – CH2-Cl        

14. An example of modified underground stem is

[A]  Carrot 

[B]  Potato 

[C]  Groundnut

[D] Turnip

Correct Answer

Correct Answer: [B]  Potato 

15. Which of the following processes makes direct use of oxygen?

[A]  Glycolysis

[B]  Fermentation

[C]  Citic Acid Cycle       

[D] Electron transport

Correct Answer

Correct Answer: [D] Electron transport

16. Crossing over occurs during meiosis at

[A]  Leptotene

[B]  Anaphase-I        

[C]  Pachytene

[D] Diakinesis

Correct Answer

Correct Answer: [C]  Pachytene

17. The well known antibiotic penicillin is obtained from this plant group:

[A]  Algae

[B]  Fungi 

[C]  Lichen 

[D] Angiosperm

Correct Answer

Correct Answer: [B]  Fungi 

18. The nature of stele in primitive vascular plants was

[A]  Protostele 

[B]  Siphonostele

[C]  Dictyostele

[D] Atactostele

Correct Answer

Correct Answer: [A]  Protostele 

19. What is a bacteriophage?

[A]  A virus

[B]  A bacterium growing in artificial nutrient medium

[C]  A fungus causing disease

[D] A phagocytic protozoa

Correct Answer

Correct Answer: [A]  A virus

20. “Particulate theory of inheritance” was pro­posed by

[A]  Charles Darwin       

[B]  Gregor Johann Mendel       

[C]  Herman Muller       

[D] T.H.Morgan

Correct Answer

Correct Answer: [B]  Gregor Johann Mendel       

21. Which one of the following animal phylum is latest by discovery?

[A]  Pogonophora

[B]  Kinorhyncha

[C]  Loricifera

[D] Ctenophora

Correct Answer

Correct Answer: [C]  Loricifera

22. A mammal that lays eggs:

[A]  Talpa

[B]  Echidna

[C]  Pteropus

[D] Lemur

Correct Answer

Correct Answer: [B]  Echidna

23. Barr body is absent in somatic cell of

[A]  Klinefelter syndrome individual

[B]  Tripple X syndrome individual

[C]  Turner syndrome individual    

[D] Sub-human mammalian female individual

Correct Answer

Correct Answer: [D] Sub-human mammalian female individual

24. 1 nm is equivalent to

[A]  1.0Å         

[B]   100Å         

[C]  10µm  

[D] .01mm

Correct Answer

Correct Answer: [A]  1.0Å         

25. Necton are

[A]  Floating organisms in water

[B]  Swimming organisms in water

[C]  Animals associated with aquatic plants

[D] Sub-merged plants in water

Correct Answer

Correct Answer: [B]  Swimming organisms in water