Easy physics problem?
2016-10-12 9:08 pm
A fire hose ejects a stream of water at an angle of 34.6 ° above the horizontal. The water leaves the nozzle with a speed of 23.2 m/s. Assuming that the water behaves like a projectile, how far from a building should the fire hose be located to hit the highest possible fire?
回答 (2)
2016-10-12 9:25 pm
✔ 最佳答案
Vo = 23.2 m/s at Θ = 34.6°Voy = Vo(sin Θ) = 13.174 m/s
Vox = Vo(cos Θ) = 19.097 m/s
time to reach max height = t = Voy/g = 13.174/9.81 = 1.3429 s
max height = H = 1/2gt² = 8.8458 m
Range = Vox • 2t = 51.2907 m
Horizontal distance from nozzle location to max height location = Range/2 ≈ 25.6 m ANS*
Assumption would be valid for water stream to behave as a projectile (actually a continuous stream of projectiles) but if such assumption is to be mentioned, the MAIN assumption applying to ALL projectile motion might also be mentioned => that this answer assumes there is "no air friction".
2016-10-12 9:10 pm
why are you posting easy questions on here
收錄日期: 2021-04-21 23:36:32
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https://hk.answers.yahoo.com/question/index?qid=20161012130853AATURLb