Newton's Laws — Set 1
Physics · न्यूटन के नियम · Questions 1–10 of 60
What is the primary physical property of an object that determines its inertia?
Correct Answer: A. Mass
Mass is the quantitative measure of an object's inertia. A larger mass results in greater resistance to changes in its state of motion. Inertia is an inherent property of matter that does not depend on gravity.
Which law states that an object at rest will remain at rest unless acted upon by an external force?
Correct Answer: B. Newton's First Law
Newton's First Law defines the concept of inertia and the necessity of force for motion change. It describes the behavior of objects in the absence of a net external force. This law is also frequently referred to as the Law of Inertia.
In the formula F = ma, what does the 'a' represent?
Correct Answer: C. Acceleration
The 'a' in the second law equation represents the acceleration produced by the net force. It indicates the rate at which the velocity of the object changes over time. Acceleration is directly proportional to force and inversely proportional to mass.
When a bus starts suddenly, passengers tend to fall backwards due to which phenomenon?
Correct Answer: D. Inertia of Rest
Inertia of rest causes the upper body to remain stationary while the lower body moves with the bus. This occurs because the body resists the sudden change from a state of rest. This is a classic everyday example of Newton's First Law.
Newton's Third Law of Motion involves how many distinct bodies?
Correct Answer: A. Two
Newton's Third Law always involves an interaction between two different bodies. When body A exerts a force on body B, body B exerts an equal force on body A. These action and reaction forces never act on the same object.
The product of mass and velocity of an object is known as what?
Correct Answer: A. Momentum
Momentum is a vector quantity calculated by multiplying an object's mass and its velocity. It represents the 'quantity of motion' possessed by a moving body. In a closed system, the total momentum remains constant during collisions.
Which of these is a non-contact force that obeys Newton's laws?
Correct Answer: A. Gravity
Gravity is a fundamental force that acts over a distance without physical contact. It provides the necessary force to accelerate objects toward the center of the Earth. According to the Second Law, this force results in the acceleration known as 'g'.
If the net force acting on a moving object is zero, what happens to its motion?
Correct Answer: B. It moves with constant velocity
An object with zero net force maintains its current state of motion according to the First Law. This means its speed and direction of travel remain completely unchanged. Constant velocity implies that the acceleration of the object is zero.
Swimming is possible due to which law of motion?
Correct Answer: B. Third Law
A swimmer pushes the water backward, and the water pushes the swimmer forward with an equal force. This demonstrates the action-reaction pair described in the Third Law. This principle is fundamental to the propulsion of all aquatic animals.
What happens to the acceleration of an object if the mass is doubled while the force remains constant?
Correct Answer: C. It is halved
The correct answer is 'It is halved'. According to the Second Law, acceleration is inversely proportional to the mass of the object. Doubling the mass while keeping force constant results in exactly half the original acceleration. This relationship helps engineers design safer and more efficient transport vehicles.