PHY 1103: Vector Analysis, Newton's Laws, and Contact Forces

Vocabulary flashcards covering vector additions, Newton's laws of motion, inertia, equilibrium, and contact forces from PHY 1103.

Scalar Quantity

A physical quantity that has only magnitude and no direction in space. Examples include mass, temperature, work, energy, time, distance, and speed.

Vector Quantity

A physical quantity that possesses both a magnitude and a direction in space. Examples include displacement, force, velocity, and acceleration.

Resolving a Vector

The mathematical process of finding the individual components of a vector along specified axes (such as the x and y axes).

Unit Vector

A vector having a magnitude of exactly $1$, commonly denoted as $\hat{x}$ along the x-direction and $\hat{y}$ along the y-direction.

Net Force

The vector sum of all external forces acting on an object, which determines the object's subsequent acceleration and motion.

Inertia

The natural property of matter describing its resistance to any changes in its velocity.

Newton's First Law of Motion

Also known as the law of inertia, it states that if a body is at rest or moving at a constant speed in a straight line, it will remain at rest or keep moving in a straight line at constant speed unless acted upon by a net force.

Free-Body Diagram (FBD)

A simplified diagram representing a single object with force vectors drawn to show every external force acting directly on that object, excluding forces exerted by the object on other things.

Equilibrium

The condition of an object when the net force acting on it is equal to zero ($\sum \mathbf{F} = 0$), causing the object to move with constant velocity or remain stationary.

Interaction Pair

A pair of equal and opposite forces exerted simultaneously by two interacting objects on each other, where each force is the interaction partner of the other.

Newton's Third Law of Motion

The principle stating that in an interaction between two objects, each object exerts a force on the other, and these two forces are equal in magnitude and opposite in direction.

Normal Force

A contact force exerted perpendicular to the contact surface that prevents two solid objects from passing through one another.

Frictional Force

A contact force that acts parallel to the contact surface and opposes relative motion or impending motion between two surfaces.

Kinetic Friction

The resistive contact force present when two surfaces are actively slipping or sliding across one another.

Static Friction

The resistive contact force that acts to prevent two surfaces from starting to slide when no relative slipping is occurring, satisfying $f_s \le \mu_s N$.