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प्रश्न
An athlete takes 2.0 s to reach his maximum speed of 18.0 km/h. What is the magnitude of this average acceleration.
उत्तर
Initial velocity, u = 0
Final velocity, v = 18 km/h = 5 m/s
Time interval, t = 2 s
Using
\[v = u + at\] , we get:
\[\text{ Acceleration } = a_{av} = \frac{\left( v - u \right)}{2} = \frac{5}{2} = 2 . 5 \text{ m} / s^2\]
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