7TH GRADE · MECHANICAL MOVEMENT
Frame of reference, trajectory and path
Relativity of movement and ways to describe body position.
The entire theory of the lesson is collected here; you can read it without an account. In interactive mode, the same theory appears as cards, followed by questions. with checking the answer and task, and progress is saved.
Basic Concepts
Mechanical movement
Changing the position of the body relative to the selected reference body over time.
The passenger is stationary relative to the seat, but moves relative to the road, so movement is always described relative to something.
Frame of reference
The body of reference, together with the coordinates and the way to measure time, forms a system for describing movement.
The choice of platform or moving car as a reference body can change the found speed and type of trajectory.
Trajectory and path
The trajectory is a line of movement, and the path is equal to the length of the section of this line traversed by the body.
A circular trajectory after a full revolution returns the body to the starting point, but the distance traveled remains positive.
Physical quantities
Path
The length of the trajectory section traversed by a moving body.
Unit: meter ·
Related formulas
The same formulas in the reference, with symbols and units.
Tasks on the topic
Statements, answer options and the walkthrough.