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munkachunka
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rower a wishes to cross a river directly to the oposite bank (east) a distance of 30mtrs (90 degree's to the shore) the current is flowing NS at 2.6m/s and he can sustain a rowing speed of 3m/s
1. calculate the direction with respect to the current flow he needs to row (degrees) in order to achieve his goal.
2. Rower B is heading south at a relative speed of 3m/s with respect to the current and his position is 80m NNE relative to rower A's start point. determine the closest point of the two rowers.
d=s/t
trig
1. time to cross 30 meters = 30m/3ms = 10 seconds.
distanced pushed to the south = 2.6m/s*10 = 26mtrs
using trig i find the angle to be 40.91.
taking north as the reference point, the angle rower a needs to go is 90-40.91 = 49.08degrees.
2. I am unsure how to find the closest point but did the following.
made the total speed equal to 3m/s+2.6m/s = 5.6m/s
The angle from rower a to rower b's start position is 22.5deg.
the NS distance between the rowers is 85.44m.
I am guessing that it has something to do with Vectors but I am unsure, could someone please check what I have done and then give me a pointer as to the correct way to approach part 2.
thankyou
Homework Statement
rower a wishes to cross a river directly to the oposite bank (east) a distance of 30mtrs (90 degree's to the shore) the current is flowing NS at 2.6m/s and he can sustain a rowing speed of 3m/s
1. calculate the direction with respect to the current flow he needs to row (degrees) in order to achieve his goal.
2. Rower B is heading south at a relative speed of 3m/s with respect to the current and his position is 80m NNE relative to rower A's start point. determine the closest point of the two rowers.
Homework Equations
d=s/t
trig
The Attempt at a Solution
1. time to cross 30 meters = 30m/3ms = 10 seconds.
distanced pushed to the south = 2.6m/s*10 = 26mtrs
using trig i find the angle to be 40.91.
taking north as the reference point, the angle rower a needs to go is 90-40.91 = 49.08degrees.
2. I am unsure how to find the closest point but did the following.
made the total speed equal to 3m/s+2.6m/s = 5.6m/s
The angle from rower a to rower b's start position is 22.5deg.
the NS distance between the rowers is 85.44m.
I am guessing that it has something to do with Vectors but I am unsure, could someone please check what I have done and then give me a pointer as to the correct way to approach part 2.
thankyou
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