Physics - May 2007

y = a sin(t -kx + )

Give the name and meaning of each symbol, and show how the frequency, wavelength, and velocity can be deduced from this equation. [30%]

Derive the Doppler shift equation:

for a sound source that is moving towards a fixed detector at velocity vs . (fo is an emitted frequency, fa is the apparent frequency, and c is the speed of sound) . [40%]

In many applications waves are transmitted from a stationary source, and reflected back by a moving object. State one such application, and write down an expression (in terms of the velocity of the moving reflector) for the frequency shift that will be detected. [30%]

2007-05-07 21:14:53 · 1 answers · asked by abdo a 1

1. Attract one another weakly
2. Repel one another weakly
3. Strongly attract or repel each other
4. Neither attracts nor repels one another

2007-05-07 21:08:55 · 4 answers · asked by ajith k 1

a bulb that has a thicker filament or the ordinary one?

2007-05-07 20:53:07 · 5 answers · asked by dULz 2

1. Bismuth
2. antimony
3. chromium
4. water

2007-05-07 20:48:38 · 3 answers · asked by ajith k 1

1. pressure waves
2. compressional waves
3. longitudinal waves
4. all the above

2007-05-07 20:41:56 · 6 answers · asked by Anonymous

I need a book or publication (written in laymans terms) to help ,me try and understand these phenomena. I have read *Abrief history of time* by Stephen Hawking and other books but *duh* I cannot get the ideas straight in my rock solid head! I am not a scientist. Just a curious guy who is an avid reader and wants to try my best to understand. I have read science fiction since the early 1950,s. I read other novels and some hard science but do not claim to understand a lot of it. Please help! I am 65 years old and this question has eaten at me for a long time. Thanks!!

2007-05-07 20:31:06 · 2 answers · asked by Anonymous

Iron, steel, aluminium, brass, lead

thank u!! (:

2007-05-07 20:25:09 · 1 answers · asked by Anonymous

Please Xplain the important relations and concepts...

2007-05-07 20:07:25 · 1 answers · asked by utkarsha.mishra 2

foam??????????????

2007-05-07 20:04:50 · 10 answers · asked by Anonymous

No big words pls

2007-05-07 19:55:36 · 7 answers · asked by Anonymous

when ever i am on a slide i get on then i get off and go to touch my mum and i electric cute her this always happens. why does this happen? this is also a qs for school which io asked about my teacher doesnt know..

confuzed mizzjordy

2007-05-07 19:31:19 · 6 answers · asked by mizz jordy =) 1

Force, weight, newton and pound? Can you explain how they are related?

2007-05-07 19:25:55 · 2 answers · asked by Anonymous

we know that e=mc^2. Here 'e' is equal to K.E + P.E. Now in case of a photon, P.E is ~ 0, then there is only K.E left which again is equals to 1/2mv^2 . Also here v = c as photon travels with the velocity of light, then it becomes as 1/2mc^2.
Now after equating this in e=mc^2 we get...

1/2mc^2 + 0 = mc^2 mc^2 gets cancelled
then
1/2 = 1
or
1=2

How is this possible?
Is this possible or I've done some mistake?
Please tell.....

2007-05-07 19:20:16 · 5 answers · asked by utkarsha.mishra 2

Let's do a thought experiment. Suppose you have two objects a few feet up from the ground, and they're casting shadows. When you move to merge these two objects, their shadows will suddenly "suck" together, just like water droplets will - their edges will meet, and suddenly the edges will expand. In effect, it looks like the shadows are fluid, merging together more than they visually should.

Can anyone explain this? I've been puzzling over this problem for a while, and it's really starting to bother me.

Thanks!

2007-05-07 18:53:59 · 3 answers · asked by Anonymous

2007-05-07 18:38:14 · 9 answers · asked by Anonymous

2007-05-07 18:31:24 · 2 answers · asked by PrettyBoy 2

2007-05-07 18:24:09 · 1 answers · asked by Anonymous

How does a vibrating lens affect the resolution of the image formed

2007-05-07 18:23:20 · 2 answers · asked by satellite406110 2

How does the position of impact of a ball on a cricket bat affect the vibration of the bat

2007-05-07 18:22:46 · 2 answers · asked by satellite406110 2

It requires energy to hold a magnet on the refigerator door. Since the magnet is losing energy it must also be losing mass according to E=mc^2.

Am I correct?

2007-05-07 17:21:57 · 10 answers · asked by Anonymous

2007-05-07 16:50:34 · 4 answers · asked by nice too meet you. 4

I need help understanding what I'm being asked. Keep it simple; I'm not a physics guy. Thanks!

Different materials respond to identical inputs of thermal energy by showing different rises in temperature. What is the modern explanation for this difference in response of materials to the same quantity of added thermal energy?

2007-05-07 16:24:59 · 4 answers · asked by Anonymous

2007-05-07 16:07:25 · 9 answers · asked by Anonymous

Isn't science just full of theories and thoughts? I mean, nothing in science is actually proven, is there? Take gravity for example, some scientists now think that the force of gravity may not even exist. Textbooks will have to be erased. What is science?

2007-05-07 15:48:47 · 7 answers · asked by The Ponderer 3

plz explain?

2007-05-07 15:45:27 · 5 answers · asked by reenu 1

its it obvious and red yellow bluee...

or is it yellow, cyan, and magenta.


those could be wrong IDK

2007-05-07 15:36:52 · 6 answers · asked by nice too meet you. 4

im asking because i think i might know how to create one using magnets. it would produce energy as long as magnets exert a force. i just want to know if someone has already thought of it or of something simulare. if you know anything about this please let me know.

2007-05-07 15:24:17 · 18 answers · asked by LUKE D 1

2007-05-07 15:23:19 · 5 answers · asked by nice too meet you. 4

I do not see how objects attain infinite mass at the speed of light: the speed of light is not infinite, because 186,000 cannot be multiplied to reach infinity. Therefore, common sense would dictate that it cannot attain infinite mass. Why is this?

2007-05-07 15:15:34 · 10 answers · asked by ? 2

Let's say that there's a huge supernova explosion in our galaxy....What are the the immediate and long term effects of that?? and in what distance range does the supernova have to be to make any effects on Earth??

2007-05-07 14:43:01 · 5 answers · asked by Maverick977 2