posted by stu .
your boat departs from the bank of a river that has a swift current parallel to its banks. if you want to cross the river in the shortest amount of time, you should direct your boat
a.) perpendicular to the current
d.) so that it drifts with the current
Whether rowing or using a motor, the boat should be aimed across the stream to cross it most quickly. It will however be carried downstream as it crosses.
A.)Perpendicular to the current
A is correct because when you point your vector perpendicular to the current and the swift is hitting it you will be able to go straight across, but A is only correct if you want to go directly across, otherwise if you just want to get to the other side in the shortest amount of time without a specific place you want to land then it is the answer D.)So that it drifts with the current.
Hopefully this was helpful and please continue to ask questions so you fully understand! Have a great day...
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