- #1
MechaMZ
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Homework Statement
At t = 0, one toy car is set rolling on a straight track with initial position 16.0 cm, initial velocity -3 cm/s, and constant acceleration 2.90 cm/s2. At the same moment, another toy car is set rolling on an adjacent track with initial position 10.5 cm, an initial velocity of 6.30 cm/s, and constant zero acceleration.
(a) At what time, if any, do the two cars have equal speeds?
The Attempt at a Solution
My answer is 1.1379s by using the method below,
Vf = Vi +at
6.3 = 3 + (2.9)t
t = 1.1379s
However, the answer is 3.21s, with the equal speeds as 12.309cm/s(I suppose by using Vf = Vi +at).
I don't understand why the final common speed is not 6.30 cm/s since the one of the object(with initial velocity of 6.30 cm/s) is moving under zero acceleration. Shouldn't it moves under a constant velocity throughout the whole journey?