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3 years ago

8

Radio wave radiation falls in the wavelength region of 10.0 to 1000 meters. What is the energy of radio wave radiation that has

a wavelength of 784 m?

1 answer:

dmitriy555 [2]3 years ago

7 0

Answer:

Explanation:

Given

Wavelength of radiation $\lambda =784\ m$

We know Energy of wave with wavelength $\lambda$ is given by

$E=\frac{hc}{\lambda }$

where h=Planck's constant

c=velocity of light

$\lambda$ =wavelength of wave

$E=\frac{6.626\times 10^{-34}\times 3\times 10^8}{784}$

$E=2.53\times 10^{-28}\ J$

Hence the energy of the wave with wavelength 784 m is $2.53\times 10^{-28}\ J$

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Answer:

The minimum angle at which the box starts to slip (rounded to the next whole number) is α=19°

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$-W_{x}+f_{s}=0$

when solving for the static friction we get:

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In the y direction we got two forces as well, the normal force and the force due to gravity, so we get:

$N-W_{y}=0$

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$N=mg cos \alpha$

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$mg cos \alpha \mu_{s}=mg sin \alpha$

we can divide both sides of the equation into mg so we get:

$cos \alpha \mu_{s}=sin \alpha$

as you may see, the angle doesn't depend on the mass of the box, only on the static coefficient of friction. When solving for $\mu_{s}$ we get:

$\mu_{s}=\frac{sin \alpha}{cos \alpha}$

when simplifying this we get that:

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$\alpha= tan^{-1}(\mu_{s})$

and we can substitute the given value so we get:

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