phy 121
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A ball is tossed upward at 15 meters / second from a height of 12 meters above the ground. Assume a uniform downward acceleration of 10 m/s^2 (an approximation within 2% of the 9.8 m/s^2 acceleration of gravity).
• How high does it rise and how long does it take to get to its highest point?
answer/question/discussion: ->->->->->->->->->->->-> :
y=(v^2-V^20) /2a
y=0-(15m/s)^2/2(9.80m/s^2)
y=11.5meters
Good.
.767 sec
This answer is incorrect. Be sure you compare with the link provided at the end of this document.
#$&*
• How fast is it then going when it hits the ground, and how long after the initial toss does it first strike the ground?
answer/question/discussion: ->->->->->->->->->->->-> :
y=v0t+1/2at^2
0=(15.0m/s)t+1/2(-9.80ms/^2)t^2
3.60seconds
11.5m/sec
the ground is not at the same height as the ball, so displacement to the ground isn't zero
#$&*
• At what clock time(s) will the speed of the ball be 5 meters / second?
answer/question/discussion: ->->->->->->->->->->->-> :
1.43seconds
#$&*
• At what clock time(s) will the ball be 20 meters above the ground?
• How high will it be at the end of the sixth second?
answer/question/discussion: ->->->->->->->->->->->-> :
1s/11.5m=.087m/seconds
.087*20=1.74seconds
11.5*6=69 meters
This answer is incorrect. Be sure you compare with the link provided at the end of this document.
#$&*
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40 minutes
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&#See any notes I might have inserted into your document. If there are no notes, this does not mean that your solution is completely correct.
Then please compare your solutions with the expanded discussion at the link
Solution
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