200 RAS Prelims MCQs on the basics of everyday science test the scientific method, the laws of motion, chemical bonding and the cell theory. The questions use daily-life examples, such as the recoil of a gun and the orbit of a satellite, and the explanations give the principle behind each example so that you can reason out similar questions.
Practice questions based on the RPSC RAS Prelims syllabus. They follow the exam pattern but are not past-paper questions.
Showing 11–20 of 200 questions
RAS PrelimsScience and Technology · Basics of Everyday Science
Q11. Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): A person sitting in a moving bus falls forward when the bus suddenly stops. Reason (R): The lower part of the body comes to rest with the bus, while the upper part tends to remain in motion due to inertia.
Explanation
Inertia causes an object to resist changes in its state of motion. When a bus stops suddenly, friction between the seat and the passenger’s lower body brings it to rest. However, the upper body continues moving forward at the previous speed due to its inherent inertia. This physical tendency explains why a person falls forward when the vehicle’s momentum is abruptly halted.
RAS PrelimsScience and Technology · Basics of Everyday Science
Q12. Newton’s second law of motion establishes a relationship between which of the following physical quantities?
Explanation
Newton’s second law of motion quantifies how the motion of an object changes when an external force is applied. It establishes that the net force acting on a body is directly proportional to its mass and the resulting acceleration. This fundamental relationship is often expressed as force equals mass times acceleration, providing a critical framework for calculating the dynamics of physical systems.
RAS PrelimsScience and Technology · Basics of Everyday Science
Q13. The recoil of a gun after firing a bullet is a practical illustration of:
Explanation
Newton’s third law states that for every action, there is an equal and opposite reaction. When a gun fires a bullet, it exerts a forward force on the projectile. Simultaneously, the bullet exerts an equal backward force on the gun. This reaction force causes the firearm to kick back or recoil, demonstrating the reciprocal nature of forces between interacting physical bodies.
RAS PrelimsScience and Technology · Basics of Everyday Science
Q14. Which of the following is defined as the product of the mass of an object and its velocity?
Explanation
Momentum is a vector quantity that represents the quantity of motion an object possesses. It is calculated by multiplying the object’s mass by its velocity. Larger masses or higher speeds result in greater momentum, making the object harder to stop. This concept is fundamental in physics for analyzing collisions and understanding how forces change the motion of objects over specific time intervals.
RAS PrelimsScience and Technology · Basics of Everyday Science
Q15. A satellite moving in a uniform circular orbit around the Earth maintains its path primarily due to:
Explanation
A satellite remains in orbit because the Earth’s gravitational pull acts as a centripetal force. This force constantly pulls the satellite toward the center of the planet, changing its direction without altering its speed. This continuous inward acceleration balances the satellite’s tangential velocity, resulting in a stable circular path that prevents it from flying off into space or crashing.
RAS PrelimsScience and Technology · Basics of Everyday Science
Q16. Match the concepts in List I with the examples in List II.
Concepts of Motion
Examples/Applications
A. Inertia of rest
i. Swimming in water
B. Inertia of motion
ii. Dust falling from a beaten carpet
C. Third law of motion
iii. Rocket propulsion
D. Conservation of momentum
iv. Athlete running past the finish line
Explanation
Inertia of rest is seen when dust falls from a carpet being beaten. Inertia of motion explains why athletes cannot stop immediately at the finish line. Swimming demonstrates the third law of motion through action-reaction forces in water. Rocket propulsion relies on the conservation of momentum as exhaust gases are ejected. These examples illustrate fundamental physical principles governing moving objects.
RAS PrelimsScience and Technology · Basics of Everyday Science
Q17. Which of the following statements about friction is incorrect?
Explanation
Friction is a force that opposes relative motion between surfaces in contact. While sliding friction occurs when one surface moves over another, rolling friction occurs when an object rolls. Rolling friction is significantly lower than sliding friction, which is why wheels move heavy loads efficiently. Additionally, sliding friction is generally less than the static friction required to initiate movement from rest.
RAS PrelimsScience and Technology · Basics of Everyday Science
Q18. Impulse is dimensionally equivalent to which of the following quantities?
Explanation
Impulse is defined as the product of the average force applied to an object and the time interval during which it acts. According to the impulse-momentum theorem, this quantity is equal to the change in the object’s momentum. Therefore, both impulse and momentum share the same physical dimensions and units, typically expressed in Newton-seconds or kilogram-meters per second in the SI system.
RAS PrelimsScience and Technology · Basics of Everyday Science
Q19. Identify the correct pair among the following:
Explanation
Newton’s first law of motion is widely recognized as the law of inertia. It states that an object will remain at rest or in uniform motion unless acted upon by an external force. This principle highlights the inherent resistance of matter to changes in its velocity. In contrast, the second law relates force to acceleration, while the third law concerns action and reaction.
RAS PrelimsScience and Technology · Basics of Everyday Science
Q20. Which of the following frames of reference is defined as one in which Newton’s first law of motion holds true?
Explanation
An inertial frame of reference is a coordinate system that is either at rest or moving at a constant velocity. In such frames, Newton’s first law of motion remains valid, meaning objects experience no acceleration unless a net force is applied. Non-inertial frames are those that are accelerating or rotating, where fictitious forces appear and the standard laws of motion require modification.
Answer key for these questions
Q
Correct answer
11
(a) Both A and R are true and R is the correct explanation of A.
12
(b) Force, mass, and acceleration
13
(c) Newton’s third law of motion
14
(d) Momentum
15
(a) Centripetal force provided by gravity
16
(a) A-ii, B-iv, C-i, D-iii
17
(b) Rolling friction is greater than sliding friction
18
(a) Change in momentum
19
(c) Newton’s First Law - Law of Inertia
20
(d) Inertial frame
Key facts from Basics of Everyday Science
Inductive reasoning draws a general conclusion from specific observations; a control variable is kept constant in an experiment; communicating the results is the last step of the scientific method.
Newton’s second law relates force, mass and acceleration; the recoil of a gun illustrates the third law.
Momentum is the product of mass and velocity; impulse is equal to the change in momentum.
A satellite in uniform circular orbit is held by the centripetal force provided by gravity.
Water (H₂O) and N₂ show covalent bonding; sodium chloride, MgO and CaF₂ are ionic.
The classical cell theory does not say that all cells have a true nucleus.
Frequently asked questions
How many RAS Prelims practice MCQs are there on Basics of Everyday Science?
This page has 200 practice MCQs on Basics of Everyday Science (Science and Technology). Each has the correct answer, and most have an explanation.
What is the product of mass and velocity called?
Momentum. Newton’s second law says that the rate of change of momentum is equal to the force applied, and impulse is equal to the change in momentum of a body.
Which law explains the recoil of a gun?
Newton’s third law of motion. The gun pushes the bullet forward, and the bullet pushes the gun back with an equal and opposite force, which is felt as recoil.
What holds a satellite in a circular orbit?
The centripetal force provided by gravity. The Earth’s pull keeps changing the direction of the satellite’s velocity so that it moves in a circle and does not fly off in a straight line.
