velocity after 2 seconds?
I assume the units are wrong: a = 2 m/s/s, not 2 m/s.
That means the each second, speed increases by 2 m/s. So, after 1 second, it’s going 2 m/s and after 2 seconds, it’s going 4 m/s. As long as the acceleration continued, each seconds would result in a gain of 2 m/s. You could just plug this into:
Vf = Vi + at.
Thus, Vi = 0 and Vf = 4 m/s.
The average speed during these 2 seconds is the average of initial and final speeds:
Vavg = (0 + 4)/2 = 2 m/s
The means that during these 2 seconds, on AVERAGE the bus was going 2 m each second. During the first second, it was going slower than 2 m/s and during the last second it was going faster than 2 m/s, but on AVERAGE, it was going 2 m each second. This is 2m + 2m = 4 m.
You could just plug the numbers into an equation:
X = Vi x t + 1/2 at^2 = 0 + 1/2 x 2 x 2^2 = 0 + 4 = 4 m
So, in conclusion:
the units needed to be corrected
Vf = 2 m/s (this is speed, which is the AMOUNT of velocity, since velocity requires a direction)
Distance = 4 m
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