AP Physics 1 / Unit 1: Kinematics
1.2 Displacement, Velocity, and Acceleration
Notes
- $\Delta x=x_f-x_i$; $\displaystyle v_{avg}=\frac{\Delta x}{\Delta t}$; $\displaystyle a_{avg}=\frac{\Delta v}{\Delta t}$.
- Constant acceleration: $v=v_0+at$, $\displaystyle x=x_0+v_0t+\frac{1}{2}at^2$, $v^2=v_0^2+2a\Delta x$.
Practice
A car speeds from 0 to 20 m/s in 4 s. Its acceleration:
$\displaystyle \frac{20}{4}$.
Starting from rest with $a=2$ m/s², the distance in 3 s:
$\displaystyle \frac{1}{2}(2)(9)$.
A ball is thrown straight up. At the top, its acceleration is:
Gravity still acts.
Ready for more? Take the Unit 1 test.