course PHY 121
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?
20cm / 2s = 10cm/s
10cm/s * 2 = 20cm/s
20cm/s 10cm/s =10cm/s / 2s =5cm/s
###This should be 10cm/s * 2 = 20cm/s
###20cm/s / 2s = 10cm/s^2
answer/question/discussion:
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?
2s * 3% = 0.06
20cm/s 0.06=19.94cm/s
5cm/s 0.06=4.94cm/s
###This should be 20cm/s / 2.06s = 9.7cm/s
###9.7cm/s * 2 =19.4
### 19.4cm/s / 2.06s =9.4
###.6cm/s^2 / 10cm/s^2=.06
answer/question/discussion:
What is the percent error in each?
0.06
###This should be 3% as well as the final 6%
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