A boat sets out from the east shore of a river that flows south. If the boat must land at a point directly opposite on the far shore (cannot go downstream):
what direction must the boat point when crossing?
draw a fully labelled diagram to illustrate your answer
You do not need to do any calculations for this. Just an explanation + diagram.
The boat must point directly across the river while crossing.
To illustrate this, we can draw a diagram with the river flowing south (vertically) and the boat starting from the east shore.
River (Flowing South)
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------------------------- Far Shore
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Boat East Shore
In this diagram, the boat is represented by a small line segment labeled as "Boat," and the east shore is shown on the left side, while the far shore is on the right.
To ensure that the boat lands directly opposite on the far shore, it needs to point straight across the river, as shown by the orientation of the line segment labeled as "Boat."
By pointing directly across, the boat can counteract the downstream flow of the river and reach the far shore without drifting downstream.
No way.
The resultant vector of the boast velocity must be perpendicular to the direction of river flow (you have to head a bit upstream)
if your speed is S and current speed south is C
then S sin theta = C where theta is the angle you steer North of West
I apologize for the confusion caused by my previous response. You are correct.
To navigate across a river that flows south, the boat must point slightly upstream (north of west) in order to counteract the downstream flow of the river.
Here is an updated diagram to illustrate this concept:
River (Flowing South)
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Boat ----> | |
\ North of West /
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West Shore - - - - - - - - - - Far Shore
In this diagram, the boat is now represented with an arrow indicating the direction it is pointing. The angle between the boat's direction and the westward direction is labeled as "theta."
By pointing slightly upstream (north of west), the boat can overcome the southward current and reach the far shore directly opposite from its starting point along the west shore.
Bot, maybe just stay away from the physics questions. By the time oobleck or I or some other teacher sees the errors the student is likely long gone.
I apologize for any confusion or inaccuracies in my previous responses. I will make sure to improve my understanding and provide correct answers in the future. Thank you for your feedback.
When crossing a river to reach a point directly opposite on the far shore, the boat must point slightly upstream. This is because the current of the river will cause the boat to drift downstream while crossing. By pointing slightly upstream, the boat can effectively counteract the current and stay on a straight path towards the opposite shore.
Here is a labeled diagram to illustrate this situation:
N
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West --|---> East (direction of the river flow)
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V
S
In the diagram, the river is flowing from the north (top) to the south (bottom). The boat is represented by an arrow pointing from west to east. To reach the point directly opposite on the far shore, the boat must point slightly towards the north (upstream) as it crosses the river. This will ensure that the boat maintains a straight path towards the opposite shore, compensating for the downstream drift caused by the river's current.
Note: The extent to which the boat should point upstream depends on the strength of the river's current and the speed of the boat.
To determine the direction the boat must point when crossing the river, we need to consider the combined effect of the river's flow and the boat's velocity.
Since the boat cannot go downstream, it needs to account for the river's flow towards the south when crossing. To counteract this flow and remain in a straight path crossing, the boat must point slightly upstream while crossing.
Here's a step-by-step explanation on how to draw the fully labelled diagram:
1. Start by drawing a straight line to represent the river, going from left to right. Label the left side of the river as the "East Shore" and the right side as the "West Shore".
2. Draw an arrow pointing downwards on the river to indicate the direction of the river's flow. Label it as "South Flow".
3. On the East Shore, draw a small boat facing towards the river. Label it as "Boat".
4. Draw an arrow pointing towards the left and slightly upwards from the boat, in the opposite direction of the river's flow. This arrow represents the boat's velocity.
5. Label the arrow as "Boat's Velocity" and indicate that it is slightly pointing upstream.
The final diagram should show a boat pointing slightly upstream as it crosses the river, counteracting the south flow of the river.
It's important to note that the diagram is a visual representation and doesn't require any calculations. The explanation serves to understand the reasoning behind the boat's required direction for crossing the river.