Final answer:
The train, starting from rest, accelerates at a rate of 3 m/s². Using the formula for final velocity in kinematics (v = u + at), we find that after 30 seconds, the train's velocity would be 90 m/s.
Step-by-step explanation:
The subject question is about calculating the final velocity of a moving object using the principles of physics. In this case, a train accelerates from rest at 3 m/s2 and we need to determine how fast it is going after 30 seconds.
As per the basic concepts of kinematics, final velocity (v) can be calculated with the formula v = u + at, where u is the initial velocity, a is acceleration and t is time. In this scenario, the train starts from rest i.e initial velocity (u=0m/s) and it accelerates at a rate of 3m/s² for a duration of 30 seconds.
By substituting the known values into the formula: v = 0 + 3(30) = 90 m/s. So, the train would be going at a speed of 90m/s after 30 seconds.
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