Understanding Motion

Physics begins with motion—the way objects move in our universe. Motion can be described by position, velocity, and acceleration. When we track how something changes its position over time, we're using the language of kinematics.

Newton’s Laws of Motion

Newton’s three laws form the backbone of mechanics:

• First Law: An object at rest stays at rest, and an object in motion stays in motion unless acted on by a force.
• Second Law: The acceleration of an object is determined by the net force acting on it and its mass (\( F = ma \)).
• Third Law: For every action, there is an equal and opposite reaction.

Types of Forces

Forces can be contact (pushes, pulls, friction) or at-a-distance (gravity, magnetism). Understanding how these interact helps explain why things move or stay still.

Energy and Work

Work is done when a force moves something. Energy comes in many forms, but in mechanics, we focus on kinetic (motion) and potential (stored) energy.

Real-life Connections

From cars speeding down highways to the way a soccer ball arcs through the air, mechanics explains everyday phenomena.