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lubasha [3.4K]
3 years ago
10

While anchored in the middle of a lake, you count exactly five waves hitting your boat every 10 s. you raise anchor and start mo

toring slowly in the same direction the waves are going. when traveling at 1.5 m/s, you notice that exactly three waves are hitting the boat from behind every 10 s. what is the speed of the waves on the lake?
Physics
1 answer:
777dan777 [17]3 years ago
7 0
<span>Every 10s 5 waves; t1 = 2s for each wave
 When v = 1.5m/s, 3 waves in 10s t2 = 10 / 3s
  Calculating the frequency in first case f1 = 5 / 10 = 0.5
 Calculating the frequency in second case f2 = 3 / 10 = 0.3
 Using the Doppler formula f = (1-v/c) f0
  For the formula f = f2, v = velocity of boat= 1.5 m/s, f0 = f1, c is velocity of wave 0.3 = 0.5 x (1 - 1.5/c) => 1.5/c = 1 - 0.6 => 1.5/c = 0.4 => c = 1.5/0.4 Velocity of the wave = 3.75 m/s</span>
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kramer

Answer:

E = 440816.32 N/C

Explanation:

Given data:

Three point charge of charge equal to +3.0 micro coulomb

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E_1 + E_3 = 0

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plugging all value

E = 2 E_2

E = 2 E_2 =\frac{2\times k \times q}{r^2}

E = \frac{2 \times 8.99 \times 10^93\times 10^{-6}}{0.35^2}

E = 440816.32 N/C

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3 years ago
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Hi there, 
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This question is solved by two top teachers as fast as they could :))
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