Q. 1
General Knowledge
Difficulty: Easy
(1 Mark)
Ordinary dry air consists of the following:
💡
Step-by-Step Explanation & Concept Rationale
Nitrogen is the most abundant gas in Earth's atmosphere, making up approximately 78% of dry air by volume.
Q. 2
General Knowledge
Difficulty: Medium
(1 Mark)
The resolving power of an electron microscope is much higher than that of an ordinary light microscope because...
💡
Step-by-Step Explanation & Concept Rationale
Resolution is inversely proportional to wavelength; electrons have much shorter de Broglie wavelengths than photons of visible light, allowing for higher resolution.
Q. 3
General Knowledge
Difficulty: Easy
(1 Mark)
On the Moon, astronauts inflate a rubber balloon with hydrogen gas and release it at a height of 2 meters. The balloon will:
💡
Step-by-Step Explanation & Concept Rationale
Since the Moon has no atmosphere, there is no air displacement or buoyant force to make the balloon float; gravity will cause it to fall.
Q. 4
General Knowledge
Difficulty: Easy
(1 Mark)
Nights are cooler in the deserts because:
💡
Step-by-Step Explanation & Concept Rationale
Sand has a low specific heat capacity and high emissivity, meaning it absorbs heat rapidly during the day and loses it just as quickly at night.
Q. 5
General Knowledge
Difficulty: Easy
(1 Mark)
If there were no atmosphere, what would be the colour of sky?
💡
Step-by-Step Explanation & Concept Rationale
The sky appears blue due to the scattering of sunlight by atmospheric gases (Rayleigh scattering); without air, no scattering occurs, leaving the sky dark.
Q. 6
General Knowledge
Difficulty: Easy
(1 Mark)
Ice skating can be used to demonstrate that when ice is under pressure, its:
💡
Step-by-Step Explanation & Concept Rationale
This phenomenon (regelation) allows a thin layer of water to form under the skate blade, acting as a lubricant.
Q. 7
General Knowledge
Difficulty: Easy
(1 Mark)
Who was the first to measure earth’s radius?
💡
Step-by-Step Explanation & Concept Rationale
The Greek mathematician Eratosthenes calculated the Earth's circumference and radius with remarkable accuracy around 240 BCE.
Q. 8
General Knowledge
Difficulty: Easy
(1 Mark)
Light travels in:
💡
Step-by-Step Explanation & Concept Rationale
Light is an electromagnetic wave where the electric and magnetic fields oscillate perpendicular to the direction of wave travel.
Q. 9
General Knowledge
Difficulty: Easy
(1 Mark)
Ozone layer prevents which of the radiation from entering the atmosphere?
💡
Step-by-Step Explanation & Concept Rationale
The ozone layer in the stratosphere absorbs approximately 98% of the Sun's medium-frequency ultraviolet light.
Q. 10
General Knowledge
Difficulty: Easy
(1 Mark)
Due to air pollution there is a gradual warming up of air. This is called:
💡
Step-by-Step Explanation & Concept Rationale
The trapping of the sun's warmth in the lower atmosphere due to greenhouse gases is the driver of global warming.
Q. 11
General Knowledge
Difficulty: Easy
(1 Mark)
The phenomenon of Aurora Borealis... display of red and green lights... is due to the radiations from:
💡
Step-by-Step Explanation & Concept Rationale
Auroras are caused by collisions between solar wind particles and oxygen/nitrogen atoms in the high-altitude ionosphere.
Q. 12
General Knowledge
Difficulty: Easy
(1 Mark)
When water boils, its temperature:
💡
Step-by-Step Explanation & Concept Rationale
At the boiling point, added thermal energy is used as latent heat to overcome molecular bonds (evaporation) rather than raising temperature.
Q. 13
General Knowledge
Difficulty: Easy
(1 Mark)
The term that best describes the shape of the earth is:
💡
Step-by-Step Explanation & Concept Rationale
The Earth's shape is specifically an oblate spheroid, often referred to as a geoid to account for local gravity variations.
Q. 14
General Knowledge
Difficulty: Easy
(1 Mark)
The lunar eclipse occurs when:
💡
Step-by-Step Explanation & Concept Rationale
A lunar eclipse happens when the Earth moves between the Sun and the Moon, casting its shadow on the lunar surface.
Q. 15
General Knowledge
Difficulty: Medium
(1 Mark)
The correct sequence of various regions in absorption spectrum is:
💡
Step-by-Step Explanation & Concept Rationale
This sequence follows the electromagnetic spectrum in order of increasing wavelength and decreasing frequency/energy.
Q. 16
General Knowledge
Difficulty: Easy
(1 Mark)
Days and nights are caused by: (1) Rotation of the earth... (2) Revolution of the earth... (3) Inclination of the earth's axis
💡
Step-by-Step Explanation & Concept Rationale
Note: While rotation is the primary cause, the key (b) includes revolution; revolution and inclination primarily cause seasonal changes.
Q. 17
General Knowledge
Difficulty: Easy
(1 Mark)
Chain reaction in a nuclear reactor is controlled by:
💡
Step-by-Step Explanation & Concept Rationale
While control rods capture neutrons, a moderator is used to slow down neutrons to ensure the chain reaction remains sustainable.
Q. 18
General Knowledge
Difficulty: Easy
(1 Mark)
As the altitude increases, the temperature decreases at the rate of 1∘C for every:
💡
Step-by-Step Explanation & Concept Rationale
This is the standard environmental lapse rate in the troposphere (roughly 6.5∘C per 1000 meters).
Q. 19
General Knowledge
Difficulty: Easy
(1 Mark)
Rate of heating and cooling of land and water is different because: 1. specific heats 2. water is mobile 3. water is transparent
💡
Step-by-Step Explanation & Concept Rationale
All three factors contribute to the thermal inertia of water compared to the rapid heating and cooling of land.
Q. 20
General Knowledge
Difficulty: Easy
(1 Mark)
X-rays and y-rays are able to destroy the living tissues by the process of:
💡
Step-by-Step Explanation & Concept Rationale
These high-energy rays are ionizing radiation, meaning they strip electrons from atoms, damaging DNA and cellular structures.
Q. 21
General Knowledge
Difficulty: Easy
(1 Mark)
Water has maximum density at:
💡
Step-by-Step Explanation & Concept Rationale
Water is most dense at 4∘C (39.2∘F); as it cools further toward freezing, it expands and becomes less dense.
Q. 22
General Knowledge
Difficulty: Easy
(1 Mark)
The non-conventional source(s) of energy is/are: (1) Biogas (2) Geothermal (3) Lignite
💡
Step-by-Step Explanation & Concept Rationale
(1) Biogas: This is a non-conventional source of energy. It is a renewable, eco-friendly energy resource produced from the anaerobic decomposition of organic matter (such as agricultural waste and manure).
(2) Geothermal: This is also a non-conventional source of energy. It taps into the natural, infinite heat generated within the Earth's crust, making it a completely renewable alternative to fossil fuels.
(2) Geothermal: This is also a non-conventional source of energy. It taps into the natural, infinite heat generated within the Earth's crust, making it a completely renewable alternative to fossil fuels.
Q. 23
General Knowledge
Difficulty: Easy
(1 Mark)
Decibel is a unit of measuring
💡
Step-by-Step Explanation & Concept Rationale
The decibel (dB) is a relative unit of measurement used to express the ratio of one value of a physical property (usually intensity) to another.
Q. 24
General Knowledge
Difficulty: Easy
(1 Mark)
‘Mica’ is extensively used in the manufacture of:
💡
Step-by-Step Explanation & Concept Rationale
Mica is an excellent electrical insulator and thermal conductor, making it ideal for use in high-voltage equipment and heaters.
Q. 25
General Knowledge
Difficulty: Easy
(1 Mark)
Which of the following is the distinctive property of a superconductor?
💡
Step-by-Step Explanation & Concept Rationale
Superconductivity is a state where a material can conduct electricity with zero energy loss below a critical temperature.
Study Stream Progress:
Showing 25 of 49 Questions (51%)
Jump to:
Ready to Test Your Retention & Speed?
Now that you have reviewed the study questions and rationales, test yourself in our interactive 1-by-1 practice engine or take the full official timed mock exam.