INTRODUCTION

What is dynamics?

- Dynamics is the study of mechanics dealing with bodies in motion.

What is statics?

- Statics is the study of mechanics dealing wtih bodies at rest

Galileo (1564-1642)

↓

Newton (1642-1727)

Dynamics

↙ ↘

Kinematics     Kinetics  

Kinematics: Motion which deals with geometric variables only- no consideration of the forces.

Kinetics: Relation between body forces, body mass, and motion of the body. Need kinematics to study kinetics.

Rigid body dynamics deals with particle motion - that is, the relation between the body and distances are relative. Particles have kinematic properties of: position, velocity, and acceleration.
Unlike the derivative concepts derived in calculus, derivatives are made with respect to a reference point or frame. This was implied in calculus, but in physics the reference frame must be explicitly defined.

There are two sets of reference frames:

1. Absolute: Never move in time (Newtonian)
2. Relative: Moves with our particle (Lagrangian)

Absolute references are typically assumed to be fixed on Earth, although with respect to the sun, it is a relative frame of reference - which grows, ad infinitum.

Most of the assumptions regarding the reference frame lead to essentially the same calculus in prerequisite math classes. However, there are some minor differences since vectors rather than scalars are now the norm.