Exams › SSC CGL (Prelims) › General › General Science
39 questions with worked solutions.
Q1. Which is generally not classified as a weather parameter?
Answer: Soil pH
Temperature, humidity, and wind are standard weather parameters because they describe atmospheric conditions. Soil pH is a property of soil, not weather. Therefore, it is not generally classified as a weather parameter.
Q2. The main objective of the National Green Hydrogen Mission is to:
Answer: Develop hydrogen as a clean energy source
The National Green Hydrogen Mission is intended to promote hydrogen as a clean and sustainable energy source. It supports decarbonization and energy transition, not nuclear, coal, or petroleum expansion.
Q3. When did India successfully conduct the first Gaganyaan TV-D1 test flight?
Answer: October 2023
India successfully conducted the first Gaganyaan TV-D1 test flight in October 2023. This was an important uncrewed test mission for validating the crew escape system and related technologies.
Answer: Both 1 and 2 are correct
Renewable Energy Certificates are issued for electricity generated from renewable sources, and they can be used by obligated entities to meet renewable purchase obligations. Hence, both statements are correct.
Q5. The approximate percentage of nitrogen in Earth’s atmosphere is:
Answer: 78%
Earth’s atmosphere is composed mainly of nitrogen and oxygen. Nitrogen makes up about 78% of the atmosphere, while oxygen is about 21%. Therefore, 78% is correct.
Q6. The speed required by a satellite to remain in a circular orbit around Earth is known as:
Answer: Critical/Orbital Velocity
The speed needed for a satellite to stay in a circular orbit around Earth is called orbital velocity, also referred to here as critical/orbital velocity. Escape velocity is the speed needed to leave Earth’s gravitational field.
Q7. Which instrument is used to measure atmospheric pressure?
Answer: Barometer
A barometer is used to measure atmospheric pressure. A hygrometer measures humidity, an ammeter measures electric current, and an altimeter measures altitude. Therefore, the correct answer is barometer.
Q8. Light pollution most severely affects observation of:
Answer: Faint galaxies and nebulae
Light pollution brightens the night sky and reduces contrast, making faint celestial objects difficult to observe. Distant galaxies and nebulae are especially affected because they emit very little light. Bright objects like the Moon are much less affected.
Q9. Spot the correct spelling of a microchip patterning technique.
Answer: Nanoimprint lithography
Nanoimprint lithography is a real micro- and nanofabrication technique used to pattern surfaces. The other options contain spelling errors.
Q10. Increased ionization in the ionosphere mainly affects:
Answer: Radio communication
The ionosphere contains charged particles that can reflect or refract radio waves. Increased ionization changes radio signal propagation and can affect communication quality. It does not directly control tides, soil fertility, or rainfall.
Q11. The Mars Orbiter Mission of India is popularly known as:
Answer: Mangalyaan
India’s Mars Orbiter Mission (MOM) is popularly called Mangalyaan. It was India’s first interplanetary mission and successfully entered Mars orbit. The other options refer to different space missions or are incorrect.
Q12. Which mission is India’s first solar mission?
Answer: Aditya-L1
Aditya-L1 is India’s first dedicated solar mission. Chandrayaan-1 is a lunar mission, Mangalyaan is a Mars mission, and Astrosat is an astronomy satellite.
Answer: Both 1 and 2 are correct
Polar satellites generally operate in low Earth orbit and are especially useful for Earth observation, weather monitoring, and remote sensing. Hence, both statements are correct.
Answer: Vitamin C
Ascorbic acid is Vitamin C. A deficiency of Vitamin C causes scurvy, which is characterized by bleeding gums, weakness, and poor wound healing.
Q15. Which of the following sequences correctly represents the flow of energy in an ecosystem?
Answer: Producer → Consumer → Decomposer
In an ecosystem, producers capture solar energy and pass it to consumers through food chains. Decomposers break down dead matter at the end of the cycle, so the correct sequence is producer to consumer to decomposer.
Q16. The International Space Station orbits Earth at roughly:
Answer: 400 km
The International Space Station is in low Earth orbit at an altitude of roughly 400 km. This is much lower than geostationary satellites, which orbit at about 36,000 km.
Answer: A - 1, B - 2, C - 3
The law of constant proportions was given by Joseph Proust, the law of multiple proportions by John Dalton, and the law of conservation of mass by Antoine Lavoisier. Hence the correct matching is A-1, B-2, C-3.
Q18. In the context of light, the splitting of white light into its constituent colours is known as:
Answer: Dispersion
The splitting of white light into its constituent colours is called dispersion. It occurs because different colours refract by different amounts in a medium like a prism.
Q19. Which hormone is often called the "Emergency Hormone"?
Answer: Adrenaline
Adrenaline is called the emergency hormone because it is secreted in stressful or dangerous situations. It prepares the body for immediate action by increasing heart rate and energy availability.
Q20. Which is NOT caused by geomagnetic storms?
Answer: Earthquakes
Geomagnetic storms can disrupt GPS, radio communication, and power grids because they affect Earth's magnetic environment and ionosphere. Earthquakes are caused by tectonic processes, not geomagnetic storms.
Q21. Find the odd one out: Mercury, Venus, Earth, Moon, Mars
Answer: Moon
Mercury, Venus, Earth, and Mars are planets, while the Moon is a natural satellite. Therefore, Moon is the odd one out.
Answer: Chlorophyll
Kidney, liver, and heart are human organs. Chlorophyll is a green pigment found in plants, so it does not belong to the group.
Answer: Liquid Propulsion Systems Centre
The Liquid Propulsion Systems Centre (LPSC) is ISRO's centre for development of liquid and cryogenic propulsion systems and liquid stages. The other centres handle launch operations, remote sensing, or telemetry and tracking.
Answer: 100 km
The commonly accepted boundary is the Kármán line, placed at about 100 km above Earth's surface. It is widely used to define the start of outer space.
Answer: Thermal Power
Wind energy, solar energy, and hydropower are renewable sources of energy. Thermal power is generally generated using coal, gas, or other fossil fuels, so it is non-renewable and different from the others.
Q26. A satellite in geostationary orbit must revolve around the Earth in approximately ____.
Answer: 24 hours
A geostationary satellite has an orbital period equal to Earth's rotation period. Since Earth rotates once in about 24 hours, the satellite must also revolve in approximately 24 hours.
Q27. Which optical device uses a convex mirror to provide a wider field of view?
Answer: Rearview mirror of vehicles
Convex mirrors provide a wider field of view because they diverge reflected rays and form upright, diminished images. This is why they are used as rearview mirrors in vehicles.
Answer: Both A and R are true and R explains A
Cryogenic engines are used in upper stages because they are highly efficient and provide the high specific impulse needed for placing heavy payloads into geostationary orbit. Thus, both the assertion and reason are true, and the reason correctly explains the assertion.
Answer: 12
The Universal Immunisation Programme covers 12 vaccine-preventable diseases for free immunization across national and sub-national levels. This makes 12 the correct option.
Q30. Why is tungsten used almost exclusively for the filament of incandescent electric lamps?
Answer: It has a high melting point and high resistivity
Tungsten is used because it can withstand very high temperatures without melting, and its relatively high resistivity helps it heat up and glow. These properties make it ideal for incandescent lamp filaments.
Answer: Both A and R are true, and R is the correct explanation of A.
Both statements are true. In Antarctic spring, sunlight returns after the polar winter and activates chlorine compounds formed on PSCs, causing rapid ozone destruction. Thus, the reason correctly explains the assertion.
Q32. A key characteristic of nuclear fusion is that:
Answer: Two light nuclei combine to form a heavier nucleus
Nuclear fusion is the process in which two light atomic nuclei combine to form a heavier nucleus, releasing a large amount of energy. It is different from nuclear fission, where a heavy nucleus splits.
Answer: Both A and R are true, and R is the correct explanation of A
BARC is indeed India's leading nuclear research institution. Its work in peaceful nuclear energy and reactor technology explains its premier status, so both statements are true and the reason correctly explains the assertion.
Q34. Which of the following statements about M.S. Swaminathan is correct?
Answer: He is known as the "Father of the Green Revolution" in India
M.S. Swaminathan is widely regarded as the Father of the Green Revolution in India. His work helped transform Indian agriculture through improved crop varieties and modern farming methods.
Q35. What does the "GSLV" rocket stand for?
Answer: Geosynchronous Satellite Launch Vehicle
GSLV stands for Geosynchronous Satellite Launch Vehicle. It is an Indian launch vehicle designed to place satellites into geosynchronous transfer orbit.
Answer: Beta-minus decay
In beta-minus decay, a neutron in the nucleus changes into a proton, an electron, and an antineutrino. This increases the atomic number by one while the mass number remains unchanged.
Q37. Find the odd one out. Sodium, Calcium, Iron, Oxygen
Answer: Oxygen
Sodium, calcium, and iron are metals. Oxygen is a non-metal, so it is the odd one out.
Q38. The key quantity allowing a satellite to sustain orbit without ongoing thrust is:
Answer: Orbital velocity
A satellite remains in orbit because it has the correct orbital velocity, which allows gravity to act as the centripetal force. Without this speed, it would either fall back to Earth or move away from orbit.
Q39. Roughly what proportion of Earth's atmosphere is made up of nitrogen?
Answer: 78%
Nitrogen is the most abundant gas in Earth's atmosphere by volume, making up about 78%. Oxygen is about 21%, and the remaining gases form a very small fraction. Hence, 78% is correct.