AP Physics 1 equations unit 1

average velocity equation

v = Δx/Δt

average speed

s = d/t

what is change in position

displacement = Δx

on a position vs time graph…

1. positive slope means going away from the origin

2. negative slope means going towards origin

3. straight line means constant velocity

4. horizontal line means no motion, velocity is 0

on a velocity vs time graph…

1. positive (above x-axis) means away from origin

2. negative (below x-axis) means towards origin

3. area under the curve gives the displacement

acceleration equation

a = Δv/Δt

vector quantity

has magnitude and direction (displacement, velocity, acceleration)

magnitude

how much

scalar quantity

has magnitude only (speed, distance travelled)

four equations to know

v_f = at + v_i

Δx = ½ a t² + v_it

v_f² = v_i² + 2a(Δt)

v = (v_{i +} v_f ) / 2