What is the average acceleration of a car that is initially at rest at a stoplight and then accelerates to 24 m/s in 9.4 s? a. 0.39 m/s2 b. 2.6 m/s2 c. 5.2 m/s2 d. 8.2 m/s2

B) a= 2.6 m/s²

Explanation:

Conceptual analysis:

Because the car moves with uniformly accelerated movement, we apply the following formula :

vf= v₀+a*t Formula (1)

Where:    

t : time in seconds (s)

v₀: initial speed in m/s  

vf: final speed in m/s  

a: acceleration in m/s²

Known Data

v₀=0

vf = 24 m/s

t=  9.4

Development problem

We replace the data in the formula (1)

vf= v₀+a*t

24 m/s = 0 + a*9.4s

a =  (24 m/s) / (9.4s)

a= 2.6 m/s²

the answer is b, have negligible mass