course Phy 201 Problem 1 Version 8If the velocity of the object changes from 3 cm / sec to 11 cm / sec in 9 seconds, then at what average rate is the velocity changing? 'dv/'dt = averate 11cm/s - 3cm/s = 8cm/s = 'dv 8cm/s / 9s = .89m/(s^2) =average rate A ball rolling from rest down a constant incline requires 8.6 seconds to roll the 68 centimeter length of the incline. * What is its average velocity? vAve = 'ds/'dt vAve = 68cm/8.6s vAve = 7.9cm/s An object which accelerates uniformly from rest will attain a final velocity which is double its average velocity. * What therefore is the final velocity of this ball? vFinal = 2* vAve vFinal = 2*7.9cm/s = 15.8cm/s * What average rate is the velocity of the ball therefore changing? 'dv/'dt = averate averate = 15.8cm/s / 8.6s averate = 1.84 (cm/s^2) An automobile accelerates uniformly down a constant incline, starting from rest. It requires 15 seconds to cover a distance of 172 meters. At what average rate is the velocity of the automobile therefore changing? vAve = 172m/15s vAve = 11.47m/s averate = 11.47m/s / 15s averate = .76m/(s^2)