Therefore the solution of this question is the velocity of roller coaster after 3 second is 22 m/s
The rate at which an object's position is changing as perceived from a given point of view and as described by a certain unit of time is known as its velocity.
Here,
The speed of roller coaster is 4m/s
The acceleration of roller coaster is 6m/s2
So,
we have to find the velocity after 3 second
thus we use the formula v=u + at
Putting values
=> v = 4 +6*3
=> v = 4 + 18
=> v = 22 m/s
Therefore the velocity of roller coaster after 3 second is 22 m/s
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