Maya is 6 km offshore on a boat at point B and wishes to reach a coastal village
which is 4 km down the straight shoreline at point D from the point A on the shore
nearest to the boat. She can row at 5 km/hour and run 7 km/hour. Point C is where she should land her boat to reach the village in the least amount of time.
a) Draw a labeled diagram for this problem, which includes points A, B, C, and D.
Let x be the distance between points A and C.
帮忙翻译一下题目,我就是读不明白这个人的位置究竟在哪还有那条海岸线在哪??
这个图的位置大概是什么样子的???
b) What two assumptions should you make about the wind and the water?
c) State the following quantities:
running distance = running time =
rowing distance = rowing time =
d) How far away is point C from point A accurate to 2 decimal places?
谢谢!!
很着急的!!谢谢
MAYA在距岸6km的船上B点,他想到沿岸的村庄,此村在从小船到岸最近点A沿岸线向下游4km的D点,她划船5km/h, 水 航速7km/h,C点是她花最少时间抵达村庄的小船登陆点。
此题是高中物理题。矢量合成问题。 划船速度5,风流作用2 直线向岸划用时最少,用时=6/5=1.2hour,水流的航程=1.2x2=2.4km CD=4-2.4=1.6km
b)假设: 实际航行速度7km/h 如果是单独由水流造成是非常好做的,如果是风促使的或风流的合力作用就比较麻烦了,
c)running distance = 根号192/5 running time =1.2
rowing distance = 5 rowing time =1.2
d)1.6