KINEMATICS LESSON 1 Part 1

Title: Kinematics

Kinematics is a branch of mechanics in physics focused on the motion of objects without considering forces that produce the motion.

Definition: Motion is the change in position of an object over time with respect to a reference point.
Objects are in motion if they change position relative to a fixed object (e.g., a tree).

Definition: A frame of reference is the viewpoint of the observer of motion, allowing specification of the location of objects.
Example: A passenger in a moving train is stationary with respect to the train but is moving with respect to the ground.
- When seated, the passenger observes no movement relative to the train but is moving relative to the railroad.

Passenger searching for a seat in a moving train.
Another example: Dribbling a ball on a table inside the moving train as an observer.
Changes in frames of reference can modify how motion is perceived, such as observing from within the train versus outside.

Definition: The length of the actual path traveled by an object.
Example: If a chalk piece travels from point A to point B (1.5 m), returning from B to A adds to the total distance covered.

Definition: Length and direction of the change in position measured from the starting point.
Example: For a displacement of 1.5 m east or along the positive x-axis, the direction is key to determining displacement.

Exercise 1: A group of climbers walked 10.0 km north and then 20.0 km east.
- a. Total distance: 30.0 km.
- b. Total displacement needs calculation using the Pythagorean theorem for the resultant.
Exercise 2: Walking 1.0 km north, 2.0 km east, then 4.0 km west, and 7.0 km back to the starting point.
- a. Calculate total distance covered.
- b. Calculate total displacement, noting the net movement results in zero displacement back to starting point.

Understanding kinematics and the concepts of motion, frame of reference, distance, and displacement is crucial for solving physical phenomena in science.