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Scorpion4ik [409]
3 years ago
14

In still​ water, a boat averages 18 18 miles per hour. it takes the same amount of time to travel 16 miles 16 miles ​downstream,

with the​ current, as it does 8 8 miles​ upstream, against the current. what is the rate of the​ water's current?
Physics
1 answer:
Vladimir79 [104]3 years ago
4 0
<span>The current is 6 miles per hour.
   Let's create a few equations:
 Traveling with the current:
 (18 + c)*t = 16

   Traveling against the current:
 (18 - c)*t = 8

   Let's multiply the 2nd equation by 2
 (18 - c)*t*2 = 16

   Now subtract the 1st equation from the equation we just doubled.
 (18 - c)*t*2 = 16
 (18 + c)*t = 16

   (18 - c)*t*2 - (18 + c)*t = 0
 Divide both sides by t
 (18 - c)*2 - (18 + c) = 0

   Now solve for c
 (18 - c)*2 - (18 + c) = 0
 36 - 2c - 18 - c = 0
 36 - 2c - 18 - c = 0
 18 - 3c = 0
 18 = 3c
  6 = c

   So the current is 6 mph.
   Let's verify that.
 (18 + 6)*t = 16
 24*t = 16
 t = 16/24 = 2/3

   (18 - 6)*t = 8
 12*t = 8
 t = 8/12 = 2/3

   And it's verified.</span>
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gulaghasi [49]

Answer:

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Explanation:

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n\lambda = dsin\theta

Where,

\lambda= wavelenght of light

N = a positive integer: 1,2,3...

\theta = Angle from the center of the wall to the dark spot

d= width of the slit

Replacing our values we have that for n=1,

dsin\theta = n\lambda

dsin(30)=(1)(539*10^{-9})

d=1.078*10^{-6}m

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Answer:

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FrozenT [24]

The correct answer to fill in the blank would be:

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<em></em>

I'm gonna go out on a limb here and take a wild guess:

I'm guessing that there's another question glued onto the end of this one, and it asks you to find either her displacement or her average velocity.  I'm so sure of this that I'm gonna give you the solution for that too.  If there's no more question, then you won't need this, and you can just discard it.  I won't mind.

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Displacement = (5E + 9W)

<em>Displacement = 4 blocks west</em>

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