cq_1_81

Phy 121

Your 'cq_1_8.1' report has been received. Scroll down through the document to see any comments I might have inserted, and my final comment at the end.

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A ball is tossed upward with an initial velocity of 25 meters / second. Assume that the acceleration of gravity is 10 m/s^2 downward.

• What will be the velocity of the ball after one second?

answer/question/discussion: 15 m/s

• What will be its velocity at the end of two seconds?

answer/question/discussion: 5 m/s

• During the first two seconds, what therefore is its average velocity?

answer/question/discussion: 10 m/s

• How far does it therefore rise in the first two seconds?

answer/question/discussion: 5 m

this is in error

• What will be its velocity at the end of a additional second, and at the end of one more additional second?

answer/question/discussion: -5 m/s at the end of 3 sec. and -15 m/s at the end of 4 sec.

• At what instant does the ball reach its maximum height, and how high has it risen by that instant?

answer/question/discussion: 1.25 sec and 23.44 m

this is in error

• What is its average velocity for the first four seconds, and how high is it at the end of the fourth second?

answer/question/discussion: vAve= 0 m/s and ‘ds = 20m

• How high will it be at the end of the sixth second?

answer/question/discussion: -30 m

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About 30 minutes.

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Good answers to most questions, but there some errors, a couple of which I've noted.

&#At least part of your solution does not agree with the solution and comments given at the link below. You should view the solution at that link and self-critique as indicated there.

Solution

This link also expands on these topics and alerts you to many of the common errors made by students in the first part of this course. &#