A boat crosses a river of width 174 m in which the current has a uniform speed of 1.13 m/s. The pilot maintains a bearing (i.e., the direc- tion in which the boat points) perpendicular to the river and a throttle setting to give a constant speed of 0.96 m/s relative to the wa- ter.

Question

A boat crosses a river of width 174 m in which the current has a uniform speed of 1.13 m/s. The pilot maintains a bearing (i.e., the direc- tion in which the boat points) perpendicular to the river and a throttle setting to give a constant speed of 0.96 m/s relative to the wa- ter.
What is the magnitude of the speed of the boat relative to a stationary shore observer?
Answer in units of m/s.

Scott · Answer

use Pythagoras to find the resultant 1.13^2 + .96^2 = s^2