An object is moving in a straight line with constant acceleration.Initially it is traveling at 16 m/s.Three seconds later it is traveling at 10 m/s.How far does it move during this time?
A)30 m
B)39 m
C)48 m
D)57 m

Question

Quizplus · Accepted Answer

The object decelerates at a constant rate, so we can use the equations of motion to solve this. First, find the acceleration: $a = \frac{\Delta v}{\Delta t} = \frac{10 m/s - 16 m/s}{3 s} = -2 m/s^2$. Then, use $s = ut + \frac{1}{2}at^2$ to find the distance: $s = 16 m/s \times 3 s + \frac{1}{2} \times (-2 m/s^2) \times (3 s)^2 = 48 m - 9 m = 39 m$.

An Object Is Moving in a Straight Line with Constant