Physics Lecture: Force, Motion, and Gravity

Vocabulary practice flashcards generated from the lecture transcript covering core mechanics concepts such as velocity, acceleration, inertia, momentum, Newton's laws of motion, and universal gravitation.

Deceleration

Acceleration with a negative sign that causes a body's speed or velocity to decrease in intensity.

Parasitic Forces

Resisting forces such as air friction and tire friction that oppose movement and rob objects of their motion.

Momentum

A physical vector quantity representing an object's quantity of motion and its tendency to continue moving, calculated as the product of mass and velocity ($\text{momentum} = \text{mass} \times \text{velocity}$).

Scalar

A physical quantity that requires only a single number to be fully characterized, such as mass.

Vector

A physical quantity that requires three properties to be fully characterized: magnitude (strength), direction, and sense.

Inertia

The property of a body to maintain its state of motion or momentum unless acted upon by an external force.

Newton's First Law of Motion

The principle stating that in the absence of a net force, an object maintains a constant velocity in a straight line or remains at rest.

Newton's Second Law of Motion

The principle stating that the acceleration of an object is directly proportional to the applied force and inversely proportional to its mass ($F = m \times a$).

Newton's Third Law of Motion

The principle stating that to every action, there is always an equal and opposite reaction.

Law of Conservation of Momentum

The principle that the total momentum of a system remains conserved (constant) if no external net forces act upon it.

Constant of Universal Gravitation ($G$)

A universal constant that sets the absolute intensity scale of the gravitational force, equal to approximately $6.67 \times 10^{-11}$.

Acceleration of Gravity ($g$)

The constant acceleration imparted by Earth's gravity on free-falling objects near its surface, equal to approximately $9.8\,\text{m/s}^2$.

Terminal Velocity

The constant falling speed reached when the upward force of air resistance (drag) balances the downward force of gravity, resulting in zero net force and zero acceleration.

Mass

An intrinsic defining property of a body representing the abundance of material packed inside it, which remains constant regardless of location.

Weight

The gravitational force exerted on a body, which varies depending on the object's location in a gravitational field.

Inverse Square Law

The geometric principle stating that the force of gravitational attraction between two objects is inversely proportional to the square of the distance ($d^2$) between them.