General Science - Online Test
Q1. The number of protozoa seen under 5 separate microscope slides were 3,4,5,6 and 7. The sum of squared deviations of observations from their sample mean is:
Answer : Option C
Explaination / Solution:
sum of squared deviations of observations = ∑(xi-μ)2
μ= ∑Xi/N = (3+4+5+6+7)/5= 25/5= 5
(xi-μ)= -2, -1, 0, 1, 2
∑(xi-μ)2= 4+1+0+1+4= 10
Q2. All the orbitals in the valence shell of the noble gases
Answer : Option A
Explaination / Solution:
These elements are called noble elements beacuse they contain ns2, np6 valence shell electronic configuration. A complete octet in the outermost shell makes these elements chemically stable, and therefore they do not easily react with other elements to form compounds.
Q3. What are the two categories into which infrastructure is divided
Answer : Option C
Explaination / Solution:
Infrastructure divide into two categories — economic and social.Both increasing the productivity of the factors of production and improving
the quality of life of its people.
Q4. Mean free path is the
Answer : Option D
Explaination / Solution:
the mean free path is the average distance traveled by a moving particle (such as an atom, a molecule, a photon) between successive impacts (collisions), which modify its direction or energy or other particle properties.
Q5. An age pyramid showing declining population is
Answer : Option A
Explaination / Solution:
Age pyramids having declining population is referred as contracting pyramid or orion pyramids or Urn pyramids. This kind of pyramids is formed by population having more old aged population than young age population.
Q6. In a centrally planned economy, the central problems are solved by
Answer : Option B
Explaination / Solution:
Method which can be employed to solve the central problems is the adoption of economic planning. In this method, the solution of the various basic problems is not achieved through the free working of demand for and supply of goods and factors. But to solve these problems, Government sets up a central planning authority which has been called by several names, such as planning commission, planning ministry or planning board.
Q7. Most active nitrogen fixer in Rice field is
Answer : Option C
Explaination / Solution:
Rice field contains large number of nitrogen fixing algae and bacteria. In which Aulosira fertilissima is most active nitrogen fixer in the rice field.
Q8. The arrows represent :[upward to downward]
Answer : Option C
Explaination / Solution:
The figure shows the muscular sac called the gall bladder. The duct of gall bladder (cystic duct) along with the hepatic duct from the liver forms the common bile duct.
Q9. Dispersion is
Answer : Option A
Explaination / Solution:
No Explaination.
Q10. Which of the following provides physiological barrier as innate immunity?
Answer : Option B
Explaination / Solution:
Physiological barrier is a kind of innate immunity which prevents microbial growth in the body that causes infection. Acid in stomach kill the microbes that enters the alimentary canal along with food.
