A boat is traveling upstream at 13 km/h with respect to the water of a river. The water is flowing at 9.0 km/h with respect to the ground. What are the (a) magnitude and (b) direction of the boat’s velocity with respect to the ground? A child on the boat walks from front to rear at 5.0 km/h with respect to the boat.What are the (c) magnitude and (d) direction of the child’s velocity with respect to the ground?

a) 22km/h

b) 0 degree
c) 17km/h
d) 180 degree

To find the boat's velocity with respect to the ground, we need to consider the velocities of the boat and the river water separately.

(a) The magnitude of the boat's velocity relative to the ground is the sum of its velocity relative to the water and the velocity of the water relative to the ground.

Boat's velocity relative to the ground = Boat's velocity relative to the water + Water's velocity relative to the ground

Boat's velocity relative to the ground = 13 km/h + 9.0 km/h = 22 km/h (upstream)

Therefore, the magnitude of the boat's velocity with respect to the ground is 22 km/h.

(b) The direction of the boat's velocity with respect to the ground is upstream.

To find the child's velocity with respect to the ground, we need to consider the velocities of the boat, river water, and the child separately.

(c) The magnitude of the child's velocity relative to the ground is the sum of the child's velocity relative to the boat, the boat's velocity relative to the water, and the velocity of the water relative to the ground.

Child's velocity relative to the ground = Child's velocity relative to the boat + Boat's velocity relative to the water + Water's velocity relative to the ground

Child's velocity relative to the ground = 5.0 km/h + 13 km/h + 9.0 km/h = 27 km/h (upstream)

Therefore, the magnitude of the child's velocity with respect to the ground is 27 km/h.

(d) The direction of the child's velocity with respect to the ground is upstream.