course phy201
Seed 2.1A ball starts with velocity 4 cm/sec and ends with a velocity of 10 cm/sec.
What is your best guess about the ball's average velocity?
answer/question/discussion (start in the next line):
my best guess at the balls average velocity is 4 cm/s - 10 cm/s = - 6cm/s
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#$&*
Without further information, why is this just a guess?
answer/question/discussion (start in the next line):
Without further information this would be just a guess because we are not given the total time it took for the ball to change velocities. Since average velocity is equal to the change in position / the chnage in time we are not given enough information to make it more that a guess.
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If it takes 3 seconds to get from the first velocity to the second, then what is your best guess about how far it traveled during that time?
answer/question/discussion (start in the next line):
The distance traveled = change in velocity * time. Then how far it traveled depends on the rate at which the ball was traveling. So if it went from a velocity of 3cm/s to 4 cm/ s we would subract 3cm/s -4 cm/s = -1cm/s and then multiply that by the time, which was 3 seconds to get -3cm
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At what average rate did its velocity change with respect to clock time during this interval?
answer/question/discussion (start in the next line):
average rate is equal to the change in velocity / change in time
so the average rate = change from the first velocity to the second velocity/ 3 seconds
You appear to be confusing average velocity with change in velocity. Check out the link given below.
&#Please compare your solutions with the expanded discussion at the link
Solution
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