Physics: Types of Regular Movement

Types of Motion

• A material point M is an idealization, whereas a real macroscopic body is composed of connected material points.

Translational Motion

• In translational motion, all points of the body follow the same trajectory, but are shifted relative to each other.
• During translational motion, any straight line within the body remains parallel to itself.

Rotational Motion

• In rotational motion, all points of the body move in circular paths around a common axis.

Types of Regular Movement

• Regular movement can be classified as either straight or curved, depending on the shape of the trajectory.

Material Point

• A material point is a body whose dimensions can be neglected.
• The position of a material point M in space can be determined using:
  • Three coordinates: x, y, z
  • Radius vector 𝒓, drawn from the origin to the material point M

Radius Vector and Time

• The radius vector 𝒓 changes in length and direction over time.
• The radius vector is a function of time: 𝒓 = 𝒓(𝒕)
• This equation is called the vector equation of motion.

Vector Equation of Motion

• One vector equation of motion is equivalent to three kinematic equations of motion of a point.

Trajectory and Displacement

• The continuous line described by the material point M during its movement is the trajectory.
• The length of the trajectory is the path ΔS (scalar).
• Δ𝒓 is a vector directed from the starting point of the trajectory to the end point, representing the displacement.