【出處】考題
【題目】如右圖有一球被從房子屋頂上的左端朝左方擲出，若屋頂高h，且球被擲出後1.5
秒後落到距離該房屋D=25.0m處若球落地方向與水平夾角六十度那麼H等多少？g=-9.8m/s2
http://i.imgur.com/FmsXEI2.jpg
【瓶頸】1.這個圖形是水平拋射還是
斜向拋射？
2.拋出的夾角是30度嗎？
先謝謝大家的幫忙！
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謝謝各位幫忙
我用水平拋射去做計算，答案是不對的
後來用斜向拋射去算才對
因為落地方向夾角60度，
用tan60= Vy/Vx =(Vo+gt)/(d/t)
求出Vo
帶入公式 H=Vot+(1/2)gt2
求出 H 得答案=32.3m
※ 編輯: gttv (125.227.216.247), 06/17/2015 14:27:47
※ 編輯: gttv (125.227.216.247), 06/17/2015 14:29:08
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