Initial Velocity Calculation Help: Find V0 from 9.8m & 4.7m/s/s

AI Thread Summary
To find the initial velocity of a car that decelerates at 4.7 m/s² while traveling 9.8 meters before stopping, the final velocity is zero. Using the kinematic equation, the initial velocity can be calculated as V0 = √(2 * a * d), where 'a' is the deceleration and 'd' is the distance. Substituting the values, V0 equals √(2 * 4.7 m/s² * 9.8 m), resulting in an initial velocity of approximately 9.79 m/s. This calculation confirms the initial speed of the car before braking. Understanding these principles is essential for accurate motion analysis in physics.
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A car drives at constant velocity on a road. As it comes near a stop sign, the driver brakes, which makes the car decelerate at 4.7 m/s/s. If the car traveled 9.8 METERS while the driver was braking, what was the starting or initial velocity just when the driver was hitting the brakes?

I can't find initial velocity because I can't find the final velocity here. Help please.
 
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The final velocity is zero, the car comes to a stop.
 

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