Physics Chapter on Motion and Laws

Study Notes

Everything in the universe moves, whether it's small and slow or large and fast.
Even if you appear to be standing still, the Earth is moving around the Sun, and the Sun is moving around our galaxy.

Newton's First Law: An object at rest stays at rest, and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force.
Newton's Second Law: The acceleration of an object is directly proportional to the net force acting on it and inversely proportional to its mass. This is represented by the equation F = ma.
Newton's Third Law: For every action, there is an equal and opposite reaction.

Translational Motion: An object moves along a path in any of the three dimensions, like a train moving on a track.
Random Motion: Disordered or irregular motion of a body, like the motion of gas molecules or insects.
Periodic Motion: Motion that repeats itself after certain intervals of time, like a swinging pendulum.
Wave Motion: The transfer of energy and momentum from one point to another without the actual transport of matter; for example, waves on the surface of water.
Circular Motion: The motion of an object in a circular path; examples include a car driving on a circular track, a planet orbiting the sun, or an electron orbiting the nucleus of an atom.
Vibrational Motion: The motion of a body about its mean position, like the oscillation of a pendulum.
Harmonic Motion: Any motion that can be described using sine or cosine functions.

Position: Describes the location of the object on the circular path.
Angular Velocity (ω): The rate of change of angular displacement, measured in radians per second.
Angular Acceleration (α): The rate of change of angular velocity, measured in radians per second squared.

An object moving in a circular path can be described using the following terms: position, angular velocity, and angular acceleration.
Angular velocity is a vector quantity, meaning it has both magnitude and direction. The direction is perpendicular to the plane of rotation.
Angular acceleration is the rate of change of angular velocity and is defined as the derivative of angular velocity with respect to time.

Newton's laws of motion can also be applied to circular motion.
For example, Newton's second law can be used to determine the force required to keep an object moving in a circular path.

ω = ω0 + αt (final angular velocity = initial angular velocity + angular acceleration x time)
θ = ω0t + 1/2αt^2 (angular displacement = initial angular velocity x time + 1/2 angular acceleration x time squared)
ω^2 = ω0^2 + 2αθ (final angular velocity squared = initial angular velocity squared + 2 x angular acceleration x angular displacement)