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Pupil
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posted by  zoey1912 on 2/8/2008 8:41:41 AM  |  status: Live  

Equation used for the answer

Course Textbook Chapter Problem
Calculus Based Physics Physics (7th) by Cutnell, Johnson 3 16P
Question Details:
I'm not sure why the equation g= 2vsinθ/t is used. Where does the 2 come from? I looked in my text and could not find it anywhere.
 
The question is: A golfer imparts a speed of 30.3 m/s to a ball, and it travels the max possible distance before landing on the green. The tee and the green are at the same elevation. (a) How much time does the ball spend in the air?
 
I understand the concept of the question, just not where the equation is derrived from? Thanks
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Guru
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posted by Navidd on 2/8/2008 9:13:07 AM  |  status: Live
Asker's Rating: None Provided    Moderator's Rating: Helpful
Response Details:
If it travels the max possible distance, means θ = 450 means  vx = vSin 45 = vy
a = v / T , in this case  -g = -vy / T  or g = vy / T   
This T, is the time required for the ball to reach the highest point in the air, it takes the same time for the ball to reach the ground again.
Means, t = 2T
So, g = vy / T = vx / T
g = (vx / t) / 2
g = 2vx / t
g = 2vSinθ / t
 
Hope it helps
 
Oracle
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posted by CANTIUS on 2/8/2008 9:13:34 AM  |  status: Live
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zoey1912's comment:
"You are awesome!!! Thank you so much for answering this and being so quick!! I appreciate it!!!"
Response Details:
I rarely give answers.  I try to provide solutions.
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