The acceleration of the speedboat relative to the shore is 10m/s²
Acceleration is the change in velocity of an object with respect to time. Mathematically;
Acceleration = change in velocity/Time
Change in velocity = 50 - 20
Change in velocity = 30m/s
Time = 3secs
Substitute into the formula to have:
acceleration = 30/3
acceleration = 10m/s²
Hence the acceleration of the speedboat relative to the shore is 10m/s²
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