Crave The Wave B

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Re: Crave The Wave B

Postby UTF-8 U+6211 U+662F » April 25th, 2015, 7:43 pm

Correct. Funny, it's about 0.98889 radians.
What are "the shadow zones" and why do they exist?

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Re: Crave The Wave B

Postby RontgensWallaby » April 26th, 2015, 5:22 am

ANS
[hide][/hide]Shadow zones are regions on Earth's surface which seismic waves from a given epicenter cannot reach. The S-wave shadow zone is anywhere past 104 deg and the P-wave shadow zone is between 104 deg and 140 deg. They occur because of the curving refraction of the seismic waves as they travel through the Earth's mantle and core (generally speed of sound increases as you go deeper). S-waves are stopped at the outer core, but P-waves can travel through. However, because the speed of sound in the outer core is slower, P-waves are refracted as they enter it.[hide][/hide]
Every great and deep difficulty bears in itself its own solution. It forces us to change our thinking in order to find it. - Niels Bohr

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Re: Crave The Wave B

Postby UTF-8 U+6211 U+662F » April 26th, 2015, 6:43 am

Shadow zones are regions on Earth's surface which seismic waves from a given epicenter cannot reach. The S-wave shadow zone is anywhere past 104 deg and the P-wave shadow zone is between 104 deg and 140 deg. They occur because of the curving refraction of the seismic waves as they travel through the Earth's mantle and core (generally speed of sound increases as you go deeper). S-waves are stopped at the outer core, but P-waves can travel through. However, because the speed of sound in the outer core is slower, P-waves are refracted as they enter it.
Correct, your turn!

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Re: Crave The Wave B

Postby RontgensWallaby » April 26th, 2015, 7:05 pm

Yellow light with a wavelength of 570 nm passes through a single aperture with a width of 5*10^-6 m. What is the angular distance between two consecutive maxima if the resulting diffraction pattern is projected onto a screen?
Every great and deep difficulty bears in itself its own solution. It forces us to change our thinking in order to find it. - Niels Bohr

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Re: Crave The Wave B

Postby Scioly99 » April 26th, 2015, 7:25 pm

I'm not sure if this is right, but I got 0.11425 rad

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Re: Crave The Wave B

Postby RontgensWallaby » April 27th, 2015, 2:23 pm

Correct. Your turn (whoever it is that I should be addressing)!
Every great and deep difficulty bears in itself its own solution. It forces us to change our thinking in order to find it. - Niels Bohr

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Re: Crave The Wave B

Postby Scioly99 » April 27th, 2015, 3:46 pm

A jet plane flies at a constant altitude of 700m above ground. An observer on the ground hears a sonic boom 6 seconds after the plane passes directly overhead. what is the speed of the plane? (assume that the velocity of sound in air is constant at all altitudes)

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Re: Crave The Wave B

Postby RontgensWallaby » April 27th, 2015, 6:34 pm

I've studied sonic booms before, but I don't know how to do this one... Is it...
1065.16m/s
Every great and deep difficulty bears in itself its own solution. It forces us to change our thinking in order to find it. - Niels Bohr

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Re: Crave The Wave B

Postby Scioly99 » April 27th, 2015, 7:08 pm

i Think that's right

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Re: Crave The Wave B

Postby RontgensWallaby » April 28th, 2015, 5:10 pm

In retrospect, the question is unsolvable... Try it but replace the 6s with just 1s and see how what you get compares to mine.
Every great and deep difficulty bears in itself its own solution. It forces us to change our thinking in order to find it. - Niels Bohr


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