Acceleration

What is Acceleration

● Acceleration is the change in velocity per unit time.
● Acceleration can result from

A change in speed (increase or decrease)

A change in direction (up, down, back, forth...)

Changes in both

Mr. Posada’s
Bugati

Formula

Acceleration =

Change in velocity

Change in time

a = Δv

Δt

vf - vi

=

Δt

Ariel dropped a golf ball from her second story window.

The ball starts from rest and hits the sidewalk 1.5 s later
with a velocity of 14.7 m/s. Find the average acceleration
of the golf ball.
vf - vi

Δt

14.7 m/s - 0 m/s

1.5 s

a =

= 9.8 m/s2

Carlos’s car accelerates from 30m/s (V_i) to 60 m/s (v_f)

northward in 15 seconds. What is the
acceleration of the car?

vf - vi

Δt

60 m/s - 30 m/s

15 s

a =

=

2 m/s2

Carlos’s car accelerates from 60m/s to 30 m/s

northward in 15 seconds. What is the
acceleration of the car?

vf - vi

Δt

30 m/s - 60 m/s

15 s

a =

=

-2 m/s2

Notice the negative sign! It means
the car is slowing down

Acceleration Graph

What part of the graph shows no
acceleration?

What part of the graph shows the highest
acceleration?