Some teenagers are exploring the outer perimeter of a castle. They notice a spy hole in its wall, across the moat a horizontal distance x and vertically up the wall a distance y. They decide to throw pebbles at the hole. One girl wants to use physics to throw with the minimum speed necessary to hit the hole. What is the required launch speed v and launch angle θ above the horizontal?
References
1.
See the “
Supplemental
” tab at TPT Online, https://doi.org/10.1119/1.5011825 , for the appendix.2.
Compare to Eq. (1) in
H.
Van Dael
and H.
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,” Am. J. Phys.
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, 466
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(May
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R. A.
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, 344
–347
(Sept.
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See Eq. (4) in
W. S.
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,” Phys. Teach.
15
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D. B.
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S. K.
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,” Phys. Teach.
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, 52
(Jan.
2013
).© 2017 American Association of Physics Teachers.
2017
American Association of Physics Teachers
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