This question tests the understanding of Newton's First Law of Motion, specifically the concept of inertia. When a bus suddenly stops, the passenger experiences a forward jerk due to their body's tendency to maintain its state of motion.
Correct Option: D) Inertia of motion. This is the correct explanation because the passenger's body was already in motion along with the bus, and it tends to maintain that state of motion when the bus suddenly stops.
The question asks for the correct statement of Newton's First Law of Motion. We need to recall the definitions of all three of Newton's Laws and identify which option corresponds to the First Law.
D) Every body continues in its state of rest or uniform motion in a straight line unless compelled by an external force.
This statement is the classic definition of Newton's First Law of Motion, also known as the Law of Inertia. It describes the behavior of objects in the absence of a net external force.
The question asks about the factor that determines the inertia of a body. Inertia is a fundamental property of matter that describes its resistance to changes in its state of motion. We need to identify which physical quantity directly quantifies this resistance.
Therefore, the mass of the body is the direct measure of its inertia.
Correct Option: A) Mass of the body. Mass is the quantitative measure of inertia. A body with greater mass has greater inertia.
The question describes a book at rest on a table and asks why the force exerted by the table on the book is equal and opposite to the book's weight. This scenario involves forces acting on an object that is not accelerating, which is a key concept in Newton's Laws of Motion.
A) The book is in equilibrium as per Newton's First Law — This is correct. The state of being "at rest
This phenomenon can be explained by Newton's First Law of Motion, also known as the Law of Inertia. Inertia is the tendency of an object to resist changes in its state of motion.
A) Backward — This is correct because the rider's upper body, due to inertia of rest, resists the sudden forward motion of the horse and tends to stay in its original position, causing them to fall backward relative to the horse.
The question asks for the SI unit of force. To answer this, we need to recall the standard units for various physical quantities in the International System of Units (SI).
Correct Option: A) Newton is the SI unit of force.