physics boat problem...can you please explain?

A motorboat capable of traveling 5m/s in still water, heads across a river (200m wide) at an agle of 25° upstream from directly across the river. The boat ends up 40m upstream from the 'straight across' direction when it reaches the far bank. Determine the speed of the river current.
A thorough explanation will earn you 10points. Thank you.

Dvandom2007-09-30T18:22:33Z

Favorite Answer

Use the angle to figure out the components of the boat's velocity. One will be the "across the river" speed (call it x-direction), the other will be the "upstream" speed (call it y). Once you have the x component, you can figure out how much time it took to go 200 meters in the x direction. It took the same amount of time to go 40 meters in the y direction, which will give you the overall y-speed. The difference between the boat's y-speed and the overall y-speed has to be the river's current speed.

?2016-10-20T14:06:45Z

Technically, it has to do with tension, so it is extra like an airplane wing than maximum folk think of, even yet it would not probable on Bernoulli's concept. What happens is that the area of the sail dealing with the wind as severe air tension than the area dealing with away type the wind. This creates a tension on the sail that's carried to the boat by way of the mast. whilst triangular sails have been invented approximately 2,000 years in the past, a sailboat can sail in particularly much any direction even particularly much without delay in to the wind.