1. A cab driver picks up a customer and delivers her 2.00km away, on a straight route. The driver accelerates to the speed limit and, on reaching it, begins to decelerate at once. The magnitude of the decelerates is three times the magnitude of the acceleration. Find the lengths of the acceleration and deceleration phases. *** this one i have no idea what they are talking about***(adsbygoogle = window.adsbygoogle || []).push({});

2.A speedboat starts from rest and accelerates at 2.01m/s^2 for 7.00 sec. At the end of this time, the boat conts. for an additional 6.00sec. with an acceleration of 0.518m/s^2 . Following this, the boat accelerates at - 1.49m/s^2 for 8.00 sec. (a) what is the velocity of the boat at t=21.0sec. (b) find the total displacement of the boat

** i don't know where to start cuz there so many A and V.

3. A Boeing 747 " Jumbo Jet" has a length of 59.7 m. The runway on which the plane lands intersects another runway. The width of the intersection is 25.0 m. The plane decelerates through the intersection at a rate of 5.70m/s62 and clears it with a final speed of 45.0m/s. How much time is needed for the plane to clear the intersection??

out of 20 probs..that's theonly 3 i don't understand so anyone can help i'll greatly appreciated.. thanks in advanced

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# Homework Help: Kinematics - Acceleration and deceleration

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