Grade 10 physics
Kinematics in Depth: Relativity of Motion, Acceleration, Equations of Motion
Kinematics describes how position and velocity change in a chosen reference frame without yet explaining the forces that cause the motion.
1. Core ideas and learning goals
- Position, displacement and velocity are defined only after a reference frame, origin, axis and clock have been chosen.
- Average acceleration is the change in velocity divided by the time interval; instantaneous acceleration describes the local rate of change.
- For constant acceleration, velocity changes linearly with time according to v = v0 + at.
- For constant acceleration, displacement equals v0 t + at^2/2 when measured from the initial position.
- The slope of an x-t graph is velocity, while the slope of a v-t graph is acceleration and its signed area is displacement.
2. Physical model
Kinematics describes how position and velocity change in a chosen reference frame without yet explaining the forces that cause the motion.
Kinematics describes how position and velocity change in a chosen reference frame without yet explaining the forces that cause the motion. The model links observable changes with measurable physical quantities and conservation laws.
Before applying a relation, specify the reference frame, system boundary, initial state and approximations. The conclusion is valid only while those conditions are satisfied.