A train slows from 44 m/s to 19 m/s in 9 seconds. What is the train's acceleration? Show your work.
1 answer:
Answer:
a = 2.77 [m/s²]
Explanation:
To solve this problem we must use the following equation of kinematics.
where:
Vf = final velocity = 19 [m/s]
Vo = initial velocity = 44 [m/s]
a = acceleration [m/s²]
t = time = 9 [s]
Note: The negative sign in the above equation means that the train is decreasing its velocity.
19 = 44 - a*9
9*a = 44 -19
a = 2.77 [m/s²]
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