H1 Physics 8867 · objective lesson
Kinematics, graphs and uniform acceleration
Use gradient and signed area according to the plotted quantities, and apply constant-acceleration equations only when acceleration is uniform.
Repair the common break
Common misconception: Every point on a velocity–time graph gives a distance.
Correct model: Use gradient and signed area according to the plotted quantities, and apply constant-acceleration equations only when acceleration is uniform.
Worked transfer
On a velocity–time graph rising uniformly from −2 to +6 m s⁻¹ over 4 s, acceleration is 2 m s⁻² and displacement is the signed trapezium area, 8 m. Distance requires separating the negative and positive areas.
Guided practice
Explain why “Every point on a velocity–time graph gives a distance.” fails. Then construct one example that correctly applies kinematics, graphs and uniform acceleration.
Independent practice
A velocity–time line falls from 12 to −4 m s⁻¹ in 8 s. Determine acceleration, displacement and total distance.
Return to the recorded repair plan when the explanation and application are secure enough to re-test.