21) Consider the following phenomena: 
  1. Size of the sun at dusk
  2. Colour of the sun at dawn
  3. Moon being visible at dawn
  4. Twinkle of stars in the sky
  5. Polestar being visible in the sky
Which of the above are optical illusions?
  1. 1, 2 and 3
  2. 3, 4 and 5
  3. 1, 2 and 4
  4. 2, 3 and 5

 

22) Rainbow is produced when sunlight falls on drops of rain.
Which of the following physical phenomena are responsible for this?
  1. Dispersion
  2. Refraction
  3. Internal reflection
Select the correct answer using the codes given below.
  1. 1 and 2 only
  2. 2 and 3 only
  3. 1 and 3 only
  4. 1, 2 and 3

23) The known forces of nature can be divided into four classes, viz, gravity, electromagnetism, weak nuclear force and strong nuclear force. with reference to them, which one of the following statements is not correct?
  1. Gravity is the strongest of the four
  2. Electromagnetism act only on particles with an electric charge
  3. Weak nuclear force causes radioactivity
  4. Strong nuclear force holds protons and nutrons inside the nuclear of an atom.
  

24) The efforts to detect the existence of Higgs boson particle have become frequent news in the recent past. What is /are the importance/importance of discovering this particle?
  1. It will enable us to understand as to why elementary particles have mass.
  2. It will enables us in the near future to develop the technology to transferring matter from one point to another without traversing the physical space between them.
  3. It will enable us to create better fuels for nuclear fission.
Select the correct answer using the codes given below:
  1. 1 only
  2. 2 and 3 only
  3. 1 and 3 only
  4. 1, 2 and 3


25) Consider the following animals:
  1. Sea cow
  2. Sea horse
  3. Sea lion
Which of the above is/are mammal/mammals?
  1. 1 only
  2. 1 and 3 only
  3. 2 and 3 only
  4. 1, 2 and 3

26) Which of the following diseases can be transmitted from one person to another through tattooing? 
  1. Chikungunya
  2. Hepatitis B
  3. HIV-AIDS
Select the correct answer using the codes given below

a. 1 only
b. 2 and 3 only
c. 1 and 3 only
d. 1, 2 and 3

  

27) Consider the following minerals
  1. Calcium
  2. Iron
  3. Sodium
Which of the minerals given above is/are required by human body for the contraction of muscles?
  1. 1 only
  2. 2 and 3 only
  3. 1 and 3 only
  4. 1, 2 and 3

 

28) Which of the following statements is / are correct?
  1. Viruses lack enzymes necessary for the generation of energy.
  2. Viruses can be cultured in any synthetic medium.
  3. Viruses are transmitted from one organism to another by biological vectors only.
Select the correct answer using the codes given below.
  1. 1 only
  2. 2 and 3 only
  3. 1 and 3 only
  4. 1, 2 and 3

 

29) Improper handling and storage of cereal grains and oilseeds result in the production of toxins known as aflatoxins which are not generally destroyed by normal cooking process. Aflatoxins are produced by
  1. bacteria
  2. protozoa
  3. moulds
  4. viruses

 

30) Fruits stored in a cold chamber exhibit longer storage life because
  1. exposure to sunlight is prevented
  2. concentration dioxide in the is increased of carbon environment
  3. rate of respiration is decreased
  4. there is an increase in humidity