A ball accelerates uniformly as it rolls 20 cm down a ramp, starting from rest, in 2 seconds. · What are its average velocity, final velocity and acceleration? answer/question/discussion: vAve = ‘ds/’dt = 20cm/2s = 10cm/s. vf = 2 * vAve = 2 * 10cm/s = 20cm/s a = ‘dv / ‘dt = 20cm/s / 2s = 10cm/s/s · If the time interval is in error so that it is 3% longer than the actual time interval, then what are the actual values of the final velocity and acceleration? answer/question/discussion: Is 2s – 3% = 1.94s? The final velocity would be 2 * vAve(10.31cm/s) = 20.62cm/s and a = 20.62cm/s / 1.94s = 10.63cm/s/s · What is the percent error in each? answer/question/discussion: 20cm/s/s to 20.62cm/s is a 3% error and 10cm/s/s to 10.63cm/s/s is a 6% error. I’m a little fuzzy on percentages, I divided the difference by the lower number. (.63 / 10) and converted to a percent · If the percent error is the same for both velocity and acceleration, explain why this must be so. answer/question/discussion: · If the percent errors are different explain why it must be so. answer/question/discussion: Acceleration is double the average velocity. I’m unsure exactly why though.