General Science/Everyday Science MCQs
Topic Notes: General Science/Everyday Science
MCQs and preparation resources for competitive exams, covering important concepts, past papers, and detailed explanations.
Plato
- Biography: Ancient Greek philosopher (427–347 BCE), student of Socrates and teacher of Aristotle, founder of the Academy in Athens.
- Important Ideas:
- Theory of Forms
- Philosopher-King
- Ideal State
121
Which subatomic particle is the lightest?
Answer:
Electron
The mass of an electron is approximately $9.11 imes 10^{-31}$ kg, which is about 1840 times smaller than the mass of a proton or neutron.
122
How do 'Antiviral' drugs differ from 'Antibiotics'?
Answer:
Antivirals inhibit the development of viruses, while antibiotics kill bacteria
Antibiotics kill bacteria or stop them from growing. Antivirals do not 'kill' viruses (as viruses aren't technically alive); instead, they interfere with the virus's ability to enter a host cell, replicate its genetic material, or exit the cell.
123
How is the bacterium 'Vibrio cholerae', which causes Cholera, typically transmitted to humans?
Answer:
Through contaminated food and water
Cholera is a classic waterborne disease. The bacteria are shed in the feces of infected people and can contaminate water supplies or food handled with poor hygiene. Ingesting this contaminated material leads to severe intestinal infection and rapid dehydration.
124
Which period contains the most elements?
Answer:
Period 6
Period 6 is the longest period, containing 32 elements. This includes the s-block, p-block, d-block, and the 14 f-block elements (Lanthanides).
125
Why is it important to complete a full course of antibiotics prescribed by a doctor?
Answer:
To prevent the bacteria from developing antibiotic resistance
If a patient stops taking antibiotics early, the weaker bacteria might be killed, but the more resilient ones may survive and multiply. These surviving bacteria can develop resistance to the drug, making future infections much harder to treat.
126
What is 'Absolute Zero' on the Celsius scale?
Answer:
-273.15°C
Absolute zero ($0 K$) is the theoretical temperature at which all molecular motion stops. On the Celsius scale, this corresponds to approximately -273.15°C.
127
The tendency of an atom to attract a shared pair of electrons towards itself is called:
Answer:
Electronegativity
Electronegativity is a chemical property that describes the power of an atom in a molecule to attract shared electrons to itself. Fluorine is the most electronegative element.
128
Which of these diseases is prevented by the BCG (Bacille Calmette-Guérin) vaccine?
Answer:
Tuberculosis
The BCG vaccine is primarily used against Tuberculosis (TB). It is often administered to infants and small children in countries where TB is common to protect them from severe forms of the disease, such as TB meningitis.
129
Which of the following is an example of an amorphous solid?
Answer:
Glass
Amorphous solids, like glass or plastic, lack a long-range periodic order in their atomic arrangement. Unlike crystalline solids (e.g., diamond or salt), they do not have a sharp melting point.
130
In Rutherford's gold foil experiment, why did most alpha particles pass straight through the foil?
Answer:
The atom is mostly empty space
Rutherford concluded that since the vast majority of alpha particles passed through the foil without deflection, the atom must consist mainly of empty space, with the mass concentrated in a tiny central nucleus.