Q: Ocean thermal energy is due to:

A: tides in the ocean

B: pressure difference at different levels in the ocean

C: temperature difference at different levels in the ocean

D: energy stored by waves in the ocean



Correct Option: C  [ temperature difference at different levels in the ocean ]

Remark:

Ocean Thermal Energy (OTE) is produced due to the temperature difference at different levels in the ocean. The surface water is warmer because it absorbs sunlight, while the deeper layers remain cold. This temperature gradient is used to run a heat engine that generates electricity — a process known as Ocean Thermal Energy Conversion (OTEC).

  • Tides: Related to gravitational pull, not temperature.
  • Pressure difference: Exists but not used for energy generation.
  • Waves: Used in wave energy systems, not OTEC.


Q: When Lunar Eclipse occurs ?

A: When Sun is between Earth and Moon

B: When Earth is between Sun and Moon

C: When Moon is between Earth and Sun

D: When Earth is between Sun and other celestial bodies.



Correct Option: B  [ When Earth is between Sun and Moon ]

Remark:

A Lunar Eclipse occurs when the Earth comes between the Sun and the Moon, causing the Earth’s shadow to fall on the Moon. This alignment blocks the sunlight that normally reflects off the Moon’s surface, making it appear dark or reddish (known as a Blood Moon). Lunar eclipses only occur during a full moon when the Sun, Earth, and Moon are in a straight line (or nearly so).

Other options (for context)

  • When Sun is between Earth and Moon: Incorrect — this alignment causes no eclipse.
  • When Moon is between Earth and Sun: This alignment causes a solar eclipse, not a lunar one.
  • When Earth is between Sun and other celestial bodies: Too general — lunar eclipse specifically involves the Moon.


Q: The pH of human blood is:

A: 7.2

B: 7.8

C: 6.6

D: 7.4



Correct Option: D  [ 7.4 ]

Remark:

Explanation: Human blood is maintained at a slightly alkaline pH of 7.4 (range 7.35–7.45). This balance is vital for the proper functioning of enzymes and biochemical reactions in the body. The buffer systems in blood — primarily the bicarbonate buffer system (H₂CO₃ / HCO₃⁻) — help maintain this stable pH. A small deviation from this range can lead to severe physiological disturbances.

Imbalances:

  • Acidosis: pH below 7.35 — causes drowsiness, confusion, and respiratory distress.
  • Alkalosis: pH above 7.45 — causes muscle twitching, irritability, and convulsions.


Q: What is the purpose of 'Anemometer'?

A: To measure blood pressure.

B: To measure the velocity and to find the direction of wind.

C: To measure altitude.

D: none of these.



Correct Option: B  [ To measure the velocity and to find the direction of wind. ]

Remark:

Explanation: An anemometer is a meteorological instrument used to measure wind speed and direction. It is an essential tool in weather stations, aviation, and marine forecasting.

Working Principle: The cup anemometer has three or four cups that rotate with the wind. The rotation speed is proportional to wind velocity. Advanced types also detect wind direction.

Types of Anemometers:

  • Cup: Measures wind speed using rotating cups.
  • Vane: Measures both speed and direction.
  • Hot-wire: Uses heat loss to measure air flow.
  • Ultrasonic: Uses sound waves for precise measurement.


Q: The weight of a person on the surface of the moon will be about one-sixth of his weight on the surface of the earth. This is because

A: The moon has no air.

B: The moon has no water.

C: The gravity of the moon is about half of the earth.

D: The gravity of the moon is abouut one-sixth of that of the earth.



Correct Option: D  [ The gravity of the moon is abouut one-sixth of that of the earth. ]

Remark:

Explanation: The weight of a person depends on the gravitational force exerted by a celestial body. The Moon’s gravity is only about 1/6th that of the Earth’s because it has much less mass and a smaller radius. Therefore, an object or person weighing 60 kg on Earth would weigh only about 10 kg on the Moon. Although mass remains constant everywhere, weight changes according to the local gravitational acceleration (g). Hence, lower gravity results in lower weight on the Moon.


Q: Which of the following cell organelles is referred to as the 'suicidal bags' or 'disposal units' ?

A: Lysosome

B: Peroxisomes

C: Glyoxisomes

D: Mtochondria



Correct Option: A  [ Lysosome ]

Remark:

Explanation: Lysosomes are known as the ‘suicidal bags’ or ‘disposal units’ of the cell because they contain powerful digestive enzymes capable of breaking down worn-out cell parts, foreign substances, and even the entire cell when it becomes damaged or obsolete.


Q: What does the airbag, used for safety of car driver, contain?

A: Sodium bicarbonate

B: Sodium azide

C: Sodium nitrite

D: Sodium peroxide



Correct Option: B  [ Sodium azide ]

Remark:


Q: A network of computers and other peripherals that is confined to a relatively small space is call:

A: Local Area Network

B: Wide Area Network

C: Global Network

D: Intranet



Correct Option: A  [ Local Area Network ]

Remark:

Explanation: A Local Area Network (LAN) is a network of computers and peripherals confined to a small geographical area, such as a home, school, or office building. It enables resource sharing, file transfer, and communication among connected devices within the limited range.


Q: In a society the growth and development that meets the current human needs and also conserves natural resources for future generations is known as:

A: Green economy

B: Holistic development

C: Sustainable development

D: Subsistence agriculture



Correct Option: C  [ Sustainable development ]

Remark:

Sustainable Development refers to growth that meets the needs of the present without compromising the ability of future generations to meet their own needs. It aims to balance economic progress, social equity, and environmental protection by conserving natural resources and reducing pollution for long-term ecological stability.

  • Green economy: Focuses mainly on eco-friendly industries.
  • Holistic development: Emphasizes overall human and social growth.
  • Subsistence agriculture: Involves farming mainly for self-consumption.


Q: Which of the following pairs is incorrect ?

(A) Roentgen : X-ray

(B) Newton : Law of gravitation

(C) Faraday : Diffusion of gases

(D) Pasteur : Bacteriology



A: Roentgen : X-ray

B: Newton : Law of gravitation

C: Faraday : Diffusion of gases

D: Pasteur : Bacteriology



Correct Option: C  [ Faraday : Diffusion of gases ]

Remark:

Explanation: The incorrect pair is Faraday : Diffusion of gases. The diffusion of gases was studied and explained by Thomas Graham, not by Michael Faraday. Graham’s Law states that the rate of diffusion of a gas is inversely proportional to the square root of its density or molar mass. On the other hand, Michael Faraday is famous for his work on electromagnetism and electrolysis. The other pairs are correctly matched with their discoveries.

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