The boat is moving in still water at a speed of 5 m / s. The speed of the river is 8 m / s.

The boat is moving in still water at a speed of 5 m / s. The speed of the river is 8 m / s. What is the speed of the boat relative to the shore.

Since the boat has a speed of 5 m / s, and the speed of the river flow is 8 m / s, then in order to find out the speed of the boat relative to the bank, two cases must be taken into account: 1) if the boat is moving behind the river, then the speed of the boat relative to the coast is – 5 + 8 = 13 m / s, 2) if the boat moves against the stream of the river, then the speed of the boat relative to the shore is – 8-5 = 3 m / s.