I need help on my physics problem...?

Question

A hunter wusges to cross a river that is 1.3km wide and that flows with a speed of 6.4 km/h. The hunter uses a small powerboat that moves at a maximum speed of 14km/h with respect to the water. Draw the vectors to scale on a graph to determine the answer. What is the time necessary for crossing if the boat goes directly across the river? Answer in units of min. Your answer must be within +/- 5%

I don't get this problem... Please solve it for me or give me a way to solve this... Thanks!

Answer 1

If the water was still, then it's straightforward - divide the distance by your velocity and get time required.

However, what's happening that your powerboat is pushed by the river flow downriver. Think of a right triangle. The boat going across the river has a north vector going at 14km/hour. The river has a vector going 6.4km/hour. This is going "west" The river's vector is perpendicular to the boats journey. You have the length of the two sides of a right triangle. Compute the length of the hypotenuse and that will give you the total distance traveled, across the river, and pushed downriver by the flow, and you can now compute the total time required.

Did that make any sense?

Answer 2

the galaxies rotate at speeds inconsistent with their obvious mass is by using the fact we do see all of it. i'm concerning it as being the theoretical dark remember. There are very good proofs that shows that dark remember exist. One the is the inconsistent velocity of and obvious mass. dark remember makes up approximately 75% to eighty% of the difficulty interior the Universe...