cq_1_081

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Phy 231

Your 'cq_1_08.1' report has been received. Scroll down through the document to see any comments I might have inserted, and my final comment at the end.

** CQ_1_08.1_labelMessages **

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: ->->->->->->->->->->->-> :

After one second, the velcoity of the ball will be 15 m/s

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

answer/question/discussion: ->->->->->->->->->->->-> :

vave = (25+15)/2 = 20 m/s

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The velocity is initially 25 m/s. After 1 second the velocity is 15 m/s, as you say. After 2 seconds, the velocity will not be 20 m/s.

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'ds = 20 * 1 = 20 meters

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

answer/question discussion:

The average velocity is 20 m/s

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The average velocity for the first second of motion will be 20 m/s.

The object is slowing, so average velocity for the first two seconds of motion will be less than this.

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

answer/question/discussion: ->->->->->->->->->->->-> :

Vave = (25+15)/2

'ds = 15 * 2 = 30 m

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

answer/question/discussion: ->->->->->->->->->->->-> :

After 4 seconds, the velocity will be -15ms

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

answer/question/discussion: ->->->->->->->->->->->-> :

The ball reaches its max height when its reaches rest, 0. 12.5 m/s * 2.5 s = 31.25

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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: ->->->->->->->->->->->-> :

The average is -7.5m/s

-7.5 * 4 = -30 m

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

answer/question/discussion: ->->->->->->->->->->->-> :

Vf = -35 m/s

vave = -5 m/s

So, 05* 6 = -30 m

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** **

35 min

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You'll need to rework some of these results. I've noted a couple of errors; you'll need to identify and correct any additional errors as well.

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