Railway recruitment covers several exams with overlapping syllabi, so one round of preparation serves RRB NTPC, Group D, ALP, Junior Engineer and Technician. Questions here cover mathematics, general intelligence and reasoning, general science, and general awareness including current affairs. The science section is pitched at the level the RRB papers use, which is closer to school syllabus than to competitive exam theory.
Pure water is neutral with a pH value of 7 at 25°C. Values below 7 are acidic and above 7 are basic.
Q.2Medium
How many bones are there in the adult human body?
Answer: B
An adult human body has 206 bones. Infants are born with approximately 270 bones, many of which are cartilage.
Q.3Medium
Which gas is primarily responsible for global warming?
Answer: C
Carbon dioxide (CO2) is the primary greenhouse gas responsible for global warming, released mainly through fossil fuel combustion.
Q.4Medium
What is the SI unit of force?
Answer: B
Newton (N) is the SI unit of force. 1 Newton = 1 kg·m/s². Dyne is CGS unit, Joule is energy, Pascal is pressure.
Q.5Medium
Which of the following is a conductor of electricity?
Answer: C
Copper is an excellent conductor of electricity due to free electrons. Rubber, plastic, and ceramic are insulators.
Q.6Medium
The freezing point of water at standard atmospheric pressure is:
Answer: D
All three represent the same freezing point of water: 0°C, 32°F, and 273.15 K are equivalent.
Q.7Medium
Which vitamin is produced by our skin when exposed to sunlight?
Answer: D
Vitamin D is synthesized by our skin when exposed to ultraviolet-B (UVB) radiation from sunlight.
Q.8Medium
What is the process by which water changes from liquid to gas?
Answer: C
Evaporation is the process where liquid water turns into water vapor/gas. This occurs at any temperature on the water's surface.
Q.9Medium
Which of the following is a scalar quantity?
Answer: C
Distance is a scalar quantity as it has only magnitude. Velocity, acceleration, and displacement are vectors as they have both magnitude and direction.
Q.10Medium
What is the process by which plants make their own food using sunlight?
Answer: B
Photosynthesis is the process where plants convert sunlight, water, and carbon dioxide into glucose and oxygen.
Q.11Medium
Which metal is liquid at room temperature?
Answer: B
Mercury is the only metal that remains liquid at room temperature (25°C). Its melting point is -38.8°C.
Q.12Medium
What is the speed of light in vacuum?
Answer: B
The speed of light in vacuum is approximately 3 × 10⁸ m/s or 299,792,458 m/s to be precise.
Q.13Medium
Which of the following vitamins helps in calcium absorption?
Answer: C
Vitamin D helps in the absorption of calcium from the intestines, essential for bone health and development.
Q.14Medium
What is the process by which solids directly convert to gases without becoming liquids?
Answer: C
Sublimation is the process where a solid directly converts to a gas. Dry ice (solid CO₂) is a common example.
Q.15Medium
Which blood group is considered a universal donor?
Answer: C
O- blood type is the universal donor as it lacks A, B, and Rh antigens on red blood cells.
Q.16Medium
What is the chemical formula for sulfuric acid?
Answer: B
Sulfuric acid is H₂SO₄, one of the most important industrial chemicals with numerous applications.
Q.17Medium
In the context of Newton's Laws of Motion, which law states that action and reaction are equal and opposite?
Answer: C
Newton's Third Law states that for every action, there is an equal and opposite reaction.
Q.18Medium
Which organ in the human body produces insulin?
Answer: B
The pancreas produces insulin, a hormone that regulates blood glucose levels. The beta cells in the pancreas secrete this hormone.
Q.19Medium
Which of the following is a renewable energy source?
Answer: C
Solar energy is renewable as the sun's energy is continuously available. Coal, petroleum, and natural gas are non-renewable fossil fuels.
Q.20Medium
Which blood group is considered a universal recipient?
Answer: C
AB blood group is the universal recipient because it has both A and B antigens, allowing it to receive blood from all groups.
