Week 2: 2D Kinematics And Dynamics

Newton's Second Law of Motion

Expresses the relationship between the forces acting on an object and its acceleration, summarized as $F = ma$.

Free Body Diagram (FBD)

A graphical representation used to visualize the EXTERNAL forces acting on a body. Excludes internal forces and forces created by the body.

Friction

A force that opposes the motion of an object, which comes in static and kinetic forms.

Tension

The force exerted along a wire, rope, or cable when it is pulled tight.

Dynamic Problem Solving Strategy

A systematic approach that includes drawing diagrams, identifying forces, applying Newton’s laws, and solving equations.

Mass

The quantity of matter in an object, typically measured in kilograms (kg).

Static Friction

Frictional force acting between two systems that are in contact and stationary relative to one another.

Kinetic Friction

Frictional force acting between two systems that are in contact and moving relative to one another.

Normal Force (FN)

The force perpendicular to the contact surfaces between two objects.

Newton's three laws of motion

Fundamental principles that describe the relationship between the motion of an object and the forces acting on it.

Contact Forces

Forces that require physical contact between objects, such as normal force and friction.

Field Forces

Forces that act at a distance, such as gravitational and electromagnetic forces.

Gravitational Force

The force between particles due to their mass, which is significantly noticeable due to the Earth's mass.

Electromagnetic Forces

Forces that arise from the attraction and repulsion of charged particles and magnetic poles.

Dynamic vs Kinematic

Dynamics is the study of why objects move, while kinematics is the study of how they move.

Inertial Reference Frame

A frame of reference in which an object remains at rest or moves at a constant velocity unless acted upon by an external force where Newton’s laws of motion are valid. This doesn’t include reference frames that are accelerating or rotating, where objects appear to experience forces that cause acceleration. Inertial frames provide a consistent way to observe motion, ensuring the laws of physics hold true.

Galilean Transformation

Equations that describe the transformation of coordinates from one reference frame to another moving at constant velocity.

Relative Velocity

The velocity of an object as observed from a particular reference frame, taking into account the motion of that frame.

Acceleration in Reference Frames

When one reference frame is moving at a constant velocity with respect to another, the acceleration of any object is the same in both frames.

Projectile Motion

The motion of an object thrown into the air with an initial velocity and follows a curved path under the influence of gravity.

Newton's First Law of Motion

An object in motion stays in motion and an object at rest stays at rest unless acted upon by an unbalanced external force.

Inertia

The tendency of an object to resist changes in its state of motion.

Spring Force

A restoring force exerted by a spring, described by the equation $F = -kx$, where $k$ is the spring constant and $x$ is the displacement from the equilibrium position.

Newton's Third Law of Motion

For every action, there is an equal and opposite reaction; when one body exerts a force on another, the second body exerts a force equal in magnitude and opposite in direction.

Centripetal Acceleration

The acceleration directed towards the center of a circular path, given by the formula $a_c = \frac{v^2}{r}$.

Uniform Circular Motion

The motion of an object traveling at a constant speed in a circular path, where its velocity vector is constantly changing direction.

System of Objects

A collection of connected or interacting objects considered together in analyzing forces.

Free Body Problem-Solving Strategy

A method for analyzing forces on an object by drawing a free body diagram and applying vector resolution in all base components.