A river that is flowing due west is crossed by a boat travelling from the south bank to the north bank. The boat can travel at 30 m/s in still water and the river is moving at 10 m/s.
Determine the resultant velocity for the boat when it is travelling downstream as it crosses the river. Please determine the magnitude only.
The boat is travelling downstream when crossing the river, which means it is moving in the same direction as the river's flow.
The resultant velocity of the boat can be calculated using the formula for relative velocity:
Resultant velocity = Boat's velocity + River's velocity
Resultant velocity = 30 m/s + 10 m/s
Resultant velocity = 40 m/s
Therefore, the magnitude of the resultant velocity for the boat when it is travelling downstream as it crosses the river is 40 m/s.