Question

Dave is riding on a straight path. After 5 s, his speed is 3.0 m/s. After 7 s, his speed is 5.0 m/s. After 10 s, his speed is 7.0 m/s. What was his acceleration from 5 s to 10 s? A. 0.67 m/s2 B. 1.0 m/s2 C. 2.0 m/s2 D. 0.8 m/s2

Answer 1

In this given problem, to solve for the acceleration we have to assume that the acceleration is constant. This assumption helps us understand that the velocity of Dave follows a linear increase and hence we can use the formula below for calculating the acceleration:

a= (Vf – Vi) / t

where

Vf = final velocity = 7.0 m / s

Vi = intial velocity = 3.0 m / s

t = time elapsed = 10 s – 5 s = 5 s

Substituting the known values into the equation:

a = (7.0 m / s – 3.0 m / s) / 5 s

a = 0.8 m / s^2

 

Answer:

D. 0.8 m/s2