得1條邊,點搵a/b/c呀=.=
有冇人可以講解/解釋下,唔該哂,聽日(星期2,11月11日)交架啦,唔該呀..
更新1:
中文版: 一架汽車以20米每秒的速率爬上斜坡。40分鐘後,這架車行走了700米(打橫計). 這架車總共行走了多高?
畢氏定理(2)文字題1題
2008-11-11 1:04 am
1.A car moving at 20m/s climbs up a slope.Afert 40 minutes, the car has got a horizontal displacement of 700m.How high has the car risen?
得1條邊,點搵a/b/c呀=.=
有冇人可以講解/解釋下,唔該哂,聽日(星期2,11月11日)交架啦,唔該呀..
得1條邊,點搵a/b/c呀=.=
有冇人可以講解/解釋下,唔該哂,聽日(星期2,11月11日)交架啦,唔該呀..
回答 (6)
2008-11-11 6:57 am
✔ 最佳答案
設斜坡為y , 高度為zy= (20) (40分鐘)
y=(20) (2400s)
y= 48000m ......... ( 成4萬8千米=_=............
y²=(700)² + x²
(48000)² = (700)² + x²
(48000)²-(700)² =x²
x= 47994.9 m (準確至一位小點)
d數字咁誇張既= ="
2008-11-10 22:58:41 補充：
y²=(700)² + z²
(48000)² = (700)² + z²
(48000)²-(700)² =z²
z= 47994.9 m (準確至一位小點)
所以這架車總共行走了47994.9米高
參考: 會考數學拿C既人~
2008-11-13 1:33 am
badmoonedtion's answer is wrong, (y^2=2303.51, so y=47.994896)
kennylai92101's answer is reasonable but also wrong, because the question is said climb up at speed 20m/second but kennylai92101 calculate at 20m/min.
kennylai92101's answer is reasonable but also wrong, because the question is said climb up at speed 20m/second but kennylai92101 calculate at 20m/min.
2008-11-11 7:31 am
爬上斜坡的距離:
40*20=800米
設該車總共行走了x米高。
x^2+700^2=800^2
x^2=640000-490000
x^2=150000
x=387.298米(取自6位有效小數)
40*20=800米
設該車總共行走了x米高。
x^2+700^2=800^2
x^2=640000-490000
x^2=150000
x=387.298米(取自6位有效小數)
參考: myself
2008-11-11 1:23 am
let the distance of climbs up a slope be x, wow high has the car risen be y.
x=20X40X60
=48km
Y^2+0.7^2=X^2
Y^2=2303.51
Y=1151.755km
the car has risen 1151.8km.
PS: Are you sure that the car moves 20m/sec? I think the answer will suit better if it uses 20m/min...it will make more sense.
x=20X40X60
=48km
Y^2+0.7^2=X^2
Y^2=2303.51
Y=1151.755km
the car has risen 1151.8km.
PS: Are you sure that the car moves 20m/sec? I think the answer will suit better if it uses 20m/min...it will make more sense.
2008-11-11 1:23 am
可5可以逆左條題目做中文
2008-11-11 1:09 am
可5可以逆左條題目做中文
收錄日期: 2021-04-26 13:34:30
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20081110000051KK00998