RPF Constable Previous Year Science MCQs: The Railway Protection Force (RPF) Constable exam is a crucial step for those aspiring to join one of India’s most respected security forces. Among the various subjects tested, Science plays a significant role in assessing candidates’ knowledge and understanding of fundamental concepts.
This article focuses on the previous year’s Science multiple-choice questions (MCQs) from the RPF Constable exam conducted in 2019. By analyzing these MCQs, candidates can gain insight into the exam pattern, improve their problem-solving skills, and enhance their readiness for the upcoming examinations.
RPF Constable Previous Year Science MCQs (2019 Exam Shifts)
The RPF Constable exam evaluates candidates on a range of subjects, including Science. This article summarizes multiple-choice questions (MCQs) from the 2019 exam shifts, providing answers and detailed explanations to enhance your understanding of key scientific concepts.
What is the term for the state of an organism when the female gamete develops into a new individual without fertilization?
- (a) Zygogenesis
- (b) Parthenogenesis
- (c) Monogamy
- (d) Syngamy
Answer: (b) Parthenogenesis.
Explanation: Parthenogenesis is a type of asexual reproduction where the female ovum develops into a complete organism without fertilization. Various organisms, such as bees and ants, reproduce using this method.
What is the common name for Periplaneta americana?
- (a) American Frog
- (b) American Cockroach
- (c) American Flatworm
- (d) American Earthworm
Answer: (b) American Cockroach.
Explanation: Periplaneta americana is scientifically known as the American Cockroach, which is widely recognized as a common pest.
What is the chemical formula of Plaster of Paris?
- (a) CaSO₄·1/2H₂O
- (b) CaSO₄
- (c) Ca₂SO₄·1/2H₂O
- (d) CaSO₄·2H₂O
Answer: (a) CaSO₄·1/2H₂O.
Explanation: The chemical formula for Plaster of Paris is CaSO₄·1/2H₂O. It is produced by heating gypsum (CaSO₄·2H₂O) at about 150°C, resulting in a powder that can be mixed with water to form a solid structure.
Which type of respiration occurs in the presence of oxygen?
- (a) Aerobic Respiration
- (b) Anaerobic Respiration
- (c) Autotrophic Respiration
- (d) Heterotrophic Respiration
Answer: (a) Aerobic Respiration.
Explanation: Aerobic respiration is the process of producing cellular energy in the presence of oxygen. It involves the breakdown of glucose to produce energy, carbon dioxide, and water.
What is the formula for frequency?
- (a) 1 / time period
- (b) time period / 2
- (c) time period
- (d) time period / 4
Answer: (a) 1 / time period.
What is the term for the unit of dynamic viscosity?
- (a) Candela
- (b) Poise
- (c) Watt
- (d) Pascal
Answer: (b) Poise.
Explanation: Poise is the CGS unit of dynamic viscosity. It is named after the French physicist Jean Léonard Marie Poiseuille, who studied the flow of fluids.
Who discovered X-rays?
- (a) Johann Wilhelm Ritter
- (b) Wilhelm Conrad Röntgen
- (c) Antoine Henri Becquerel
- (d) Isaac Newton
Answer: (b) Wilhelm Conrad Röntgen.
Explanation: Wilhelm Conrad Röntgen discovered X-rays in 1895. He noticed a form of electromagnetic radiation that could pass through objects, which he named “X-rays” due to its unknown nature.
When an object moves in a straight line, what is this type of motion called?
- (a) Uniform motion
- (b) Transverse motion
- (c) Displacement motion
- (d) Linear motion
Answer: (d) Linear motion.
Explanation: Linear motion refers to motion that occurs along a straight path. It can be analyzed mathematically as a one-dimensional motion, characterized by constant velocity.
What instrument measures heat transfer?
- (a) Hydrometer
- (b) Manometer
- (c) Calorimeter
- (d) Galvanometer
Answer: (c) Calorimeter.
Explanation: A calorimeter is an instrument used to measure the heat absorbed or released during a chemical reaction or physical change.
Which antibiotic produced by soil microorganisms is very effective for the treatment of typhoid fever?
- (a) Chloroquine
- (b) Chloramphenicol
- (c) Chlorazine
- (d) Chloroethanol
Answer: (b) Chloramphenicol.
Explanation: Chloramphenicol is a chlorine-containing antibiotic derived from soil microorganisms. It is particularly effective against typhoid fever and other serious infections.
What is the characteristic of carbon that allows it to form covalent bonds with other carbon atoms?
- (a) Electronation
- (b) Ionization
- (c) Electrolysis
- (d) Catenation
Answer: (d) Catenation.
Explanation: Catenation refers to the ability of atoms of the same element, such as carbon, to form long chains or structures. This property allows carbon atoms to bond with each other to form complex organic molecules.
Who was the chairman of the first three-member commission established to determine center-state relations in India?
Answer:
Explanation: The chairman of the first three-member commission, known as the Rajamannar Committee, was K. S. Rajamannar. The commission aimed to define the relationship between the central and state governments in India.
What is KCL in the context of electricity?
- (a) Kirchhoff’s Conductivity Law
- (b) Kirchhoff’s Converter Law
- (c) Kirchhoff’s Circuit Law
- (d) Kirchhoff’s Current Law
Answer: (d) Kirchhoff’s Current Law.
Explanation: Kirchhoff’s Current Law states that the total current entering a junction must equal the total current leaving that junction. This principle is based on the conservation of electric charge.
What is the primary purpose of the Planning Commission in India?
Answer:
Explanation: The Planning Commission was established to formulate and implement India’s Five-Year Plans, which guide economic development. It has since been replaced by the NITI Aayog to better address the changing needs of the nation.
What is the potential difference between an electrode and an electrolyte referred to as?
- (a) Diode potential
- (b) Standard electrode potential
- (c) Electrode potential
- (d) Electrical potential
Answer: (c) Electrode potential.
Explanation: The potential difference between an electrode and an electrolyte is termed electrode potential. It represents the tendency of the electrode to gain or lose electrons in a chemical reaction.
What is the name given to the imaginary line that passes through the center of a spherical mirror or lens?
- (a) Vertical axis
- (b) Pole axis
- (c) Spherical axis
- (d) Principal axis
Answer: (d) Principal axis.
Explanation: The principal axis is an imaginary line that passes through the optical center of a spherical mirror or lens, serving as a reference line for various optical calculations.
In which branch of biology is the study of tissues conducted?
- (a) Histology
- (b) Tissulogy
- (c) Anatomy
- (d) Pathology
Answer: (a) Histology.
Explanation: Histology is the branch of biology that studies the structure and function of tissues. It involves examining tissue samples under a microscope to understand their cellular organization.
What type of food chain starts with plants and producers and ends with carnivorous mammals?
- (a) Detrital food chain
- (b) Producer food chain
- (c) Grazing food chain
- (d) Decomposer food chain
Answer: (c) Grazing food chain.
Explanation: The grazing food chain begins with primary producers, such as plants, and ends with tertiary consumers, such as carnivorous mammals. These producers synthesize food through photosynthesis, which is then transferred through the food chain to herbivores and carnivores.
What process in which amino acids are polymerized to produce polypeptides is called?
- (a) Translation
- (b) Transcription
- (c) Aminosylation
- (d) Regulation
Answer: (a) Translation.
Explanation: The process by which amino acids are linked together to form polypeptides is known as translation. It occurs in the ribosome during protein synthesis, where the genetic code is translated into a polypeptide chain.
What term describes the phenomenon when angiosperms produce multiple embryos?
- (a) Nuclear embryony
- (b) Monoembryony
- (c) Polyembryony
- (d) Diembryony
Answer: (c) Polyembryony.
Explanation: Polyembryony is a phenomenon observed in some angiosperms where more than one embryo develops from a single fertilized ovule, leading to multiple seedlings.
What is formed by heating tetrafluoroethene in the presence of free radicals or persulfate catalysts?
- (a) Polyester
- (b) Nylon 6,6
- (c) Teflon
- (d) Nylon
Answer: (c) Teflon.
Explanation: Teflon is a polymer formed from tetrafluoroethene when heated with free radicals or persulfate catalysts under high pressure. It is known for its non-stick properties and is widely used in cookware.
What is the term for a substance that increases the rate of a chemical reaction without itself undergoing any permanent chemical change?
- (a) Reactant
- (b) Solvent
- (c) Catalyst
- (d) Precipitate
Answer: (c) Catalyst.
Explanation: A catalyst is a substance that accelerates a chemical reaction without undergoing any permanent change itself. It lowers the activation energy required for the reaction to occur.