- #1

Lori

## Homework Statement

A 0.14-km wide river flows with a uniform speed of 4.0 m/s toward the east. It takes 20 s for a boat to cross the river to a point directly north of its departure point on the south bank. What is the speed of the boat relative to the water?

2. Homework Equations

*I'm mostly concerned about the wording and which part of the "triangle" that the answer is referring to!*

2. Homework Equations

V = D/T

## The Attempt at a Solution

V = 0.14/20 = 7m

Hey!

Can someone help me explain how the speed of the boat relative to the water would be referring to the velocity in the y direction for the boat? How do i know that it isn't referring to the hypotenuse ? Overall, i usually get confused with the wording for "relative to _____" because I don't know which part of the triangle it would be a part of!

If i didn't know that the speed of the boat relative to the water is in the y direction, then i wouldn't know that i could just use the formula V = D/T!

For instance, I would think the boat's speed relative to the water is different from the boat's speed relative to the earth/ground

Last edited by a moderator: