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3 years ago

15

A water wave travels across a 42-meter wide pond in 7.0 seconds. The speed of the wave is _____. 292 m/s 49 m/s 6.0 m/s 0.17 m/s

2 answers:

anzhelika [568]3 years ago

8 0

Answer:

6.0 m/s

Explanation:

A water wave travels across a 42-meter wide pond in 7.0 seconds. The speed of the wave is _____.

292 m/s

49 m/s

6.0 m/s

0.17 m/s

tekilochka [14]3 years ago

7 0

   Speed = (distance covered) / (time to cover the distance).

The speed of anything that covers 42 meters in 7 seconds is

   (42 meters) / (7.0 seconds)

   = (42 / 7.0) (meters/second)

   =   6.0 m/s .

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Write equations for both the electric and magnetic fields for an electromagnetic wave in the red part of the visible spectrum th

Strike441 [17]

Answer:

$E=3.5(8.98*10^{6}x-2.69*10^{15}t)$

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Explanation:

The electric field equation of a electromagnetic wave is given by:

$E=E_{max}(kx-\omega t)$ (1)

E(max) is the maximun value of E, it means the amplitude of the wave.
k is the wave number
ω is the angular frequency

We know that the wave length is λ = 700 nm and the peak electric field magnitude of 3.5 V/m, this value is correspond a E(max).

By definition:

$k=\frac{2\pi}{\lambda}$

$k=8.98*10^{6} [rad/m]$

And the relation between λ and f is:

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$f=\frac{c}{\lambda}$

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The angular frequency equation is:

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$\omega=2\pi*4.28*10^{14}$

$\omega=2.69*10^{15} [rad/s]$

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$B=B_{max}(kx-\omega t)$ (3)

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$E_{max}=cB_{max}$

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$B_{max}=1.17*10^{-8}T$

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$B=1.17*10^{-8}(8.98*10^{6}x-2.69*10^{15}t)$ (4)

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Answer:

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