AP Physics 1 · Summary

Unit 1 summary

1. Displacement is final minus initial position; distance is the path length. Average velocity uses displacement and average speed uses distance.
2. Split vectors into components with $\cos\theta$ and $\sin\theta$, add the components, then rebuild the result with the Pythagorean theorem.
3. Velocities add as vectors across frames, $\vec v_{AC} = \vec v_{AB} + \vec v_{BC}$, so name the frame of every velocity.
4. Position-time slope is velocity; velocity-time slope is acceleration; velocity-time area is displacement, negative below the axis.
5. With constant acceleration, pick the equation that leaves out the quantity you neither know nor need.
6. In free fall the acceleration is 9.8 m/s² downward the whole time, even at the top where the velocity is zero.
7. For a projectile the horizontal velocity stays constant, the vertical motion is free fall, and time links the two.