(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A boat is crossing the river with a speed of 6.2 m/s east relative to the water. The river is flowing north at a speed of 2 m/s and is 750 m wide.

a) What is the speed of the boat relative to the Earth?

b) How much time is required to cross the river?

c) How far downriver will the boat land on the other shore?

d) If the pilot of the boat wanted to land directly across the river, how long would the trip take?

2. Relevant equations

d= rt

others stuff

3. The attempt at a solution

i got a through c quite easily, but I'm stuck with d

a) What is the speed of the boat relative to the Earth? 6.5146 m/s

b) How much time is required to cross the river? 120.9677 s

c) How far downriver will the boat land on the other shore? 241.9355 m

d) If the pilot of the boat wanted to land directly across the river, how long would the trip take?

I'm still having problem with d

this is what I tried

since the horizontal distance is 750m and the vertical distance is 241.9355m

I used pythagorean theorem to find the distance / the hypotenuse and it happened to be 788.0563m

so i used the equation d=rt again and plug in 6.5146 for the r because thats the speed of the boat relative to the earth

788.0563 = 6.5146t

t = 120.9678 s

but its wrong.

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# Crossing a river ( relative velocity problem )

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