Q: A substance used in the fire extinguisher under the trade name of Pyrene is:

A: Carbon dioxide

B: Chloroform

C: Carbon tetrachloride

D: Bleaching powder



Correct Option: C  [ Carbon tetrachloride ]

Remark:


Q: Who invented ATM ?

A: Luther George Simjian

B: Jhon Shepherd Barron

C: Douglas Brown

D: None of these



Correct Option: B  [ Jhon Shepherd Barron ]

Remark:

Explanation: The ATM (Automated Teller Machine) was invented by John Shepherd-Barron in 1967. He designed the first cash dispensing machine, which was installed by Barclays Bank in London, UK. The first ATM used special paper vouchers impregnated with a radioactive compound instead of plastic cards. The idea revolutionized the banking sector by allowing people to withdraw money anytime without visiting a bank counter. Modern ATMs now use magnetic or chip-based cards, PIN authentication, and networked systems for secure transactions.


Q: Cerebral Malaria is caused by:

A: Plasmodium vivax

B: Plasmodium malariae

C: Plasmodium falciparum

D: None of the above



Correct Option: C  [ Plasmodium falciparum ]

Remark:

Explanation: Cerebral malaria is a severe neurological complication of malaria infection caused by Plasmodium falciparum. The parasite infects red blood cells, making them sticky and causing them to block small blood vessels in the brain. This leads to high fever, seizures, coma, and can be fatal if untreated. Transmission occurs through the bite of an infected female Anopheles mosquito.


Q: A man inside a moving train tosses a coin, the coin falls behind him. The train is moving:

A: forward with a uniform speed

B: backward with a uniform speed

C: forward with deceleration

D: forward with acceleration



Correct Option: D  [ forward with acceleration ]

Remark:

Explanation: When a man inside a moving train tosses a coin and it falls behind him, it means the train is moving forward with acceleration. The coin, after being tossed, continues to move with the train’s initial velocity, but since the train speeds up, the coin appears to fall backward relative to the man.


Q: The location of where an organism lives would be best described as its:

A: niche

B: habitat

C: range

D: biome



Correct Option: B  [ habitat ]

Remark:

Explanation: The habitat of an organism is its natural living place where it finds food, water, shelter, and mates for reproduction. Examples include a pond for a frog, soil for an earthworm, and forest for a tiger. Each species has a specific habitat suited to its survival needs. The niche, on the other hand, describes the organism’s role or function in that habitat, such as how it obtains food or interacts with others.


Q: Sphygmomanometer is an instrument used for measuring

A: Heart beat

B: Vision of eyes

C: Blood Sugar

D: Blood Pressure



Correct Option: D  [ Blood Pressure ]

Remark:

Explanation: A sphygmomanometer is a medical instrument used to measure blood pressure. It consists of an inflatable cuff, a mercury or aneroid gauge, and a bulb for inflation. The cuff is wrapped around the upper arm and inflated to temporarily stop blood flow. As pressure is slowly released, readings are taken for systolic (maximum) and diastolic (minimum) pressure. Normal blood pressure for a healthy adult is about 120/80 mmHg.


Q: Helium is preferred to hydrogen in air balloons because it:

A: is cheaper

B: is less dense

C: has greater lifting power

D: does not form an explosive mixture with air



Correct Option: D  [ does not form an explosive mixture with air ]

Remark:


Q: Decibel is the unit used for

A: intensity of light

B: intensity heat

C: intensity of sound

D: frequency of radio wave



Correct Option: C  [ intensity of sound ]

Remark:

Explanation: The decibel (dB) is a unit used to measure the intensity or loudness of sound. It expresses sound level on a logarithmic scale relative to a standard reference intensity of 10-12 watt/m², which is the faintest sound the average human ear can hear. Normal conversation is around 60 dB, city traffic about 80–90 dB, and sounds above 120 dB can cause pain or hearing damage. The decibel scale helps compare very large variations in sound intensity conveniently.


Q: Plants absorb dissolved nitrates from soil and convert them into:

A: free nitrogen

B: urea

C: ammonia

D: proteins



Correct Option: C  [ ammonia ]

Remark:

Explanation: Plants absorb nitrogen from the soil mainly in the form of nitrates (NO₃⁻). Inside the plant, nitrates are reduced to nitrites (NO₂⁻) and then to ammonia (NH₃) through the action of specific reductase enzymes. The ammonia thus formed is then used to synthesize amino acids, proteins, nucleic acids, and other nitrogen-containing compounds necessary for plant growth.

Simplified Pathway:

NO₃⁻ → NO₂⁻ → NH₃ → Amino acids → Proteins


Q: Which type of fire extinguisher is used for petroleum fire?

A: Powder type

B: Liquid type

C: Soda acid type

D: Foam type



Correct Option: A  [ Powder type ]

Remark:
1...