Science Question For You
NolSinkler
On the Clorf Join Date: 2004-02-15 Member: 26560Members, Constellation
On the Clorf Join Date: 2004-02-15 Member: 26560Members, Constellation
<div class="IPBDescription">all you should be able to get it...</div> I have a science question for you...got $400 riding on this. My dad says that if I figure it out over the next DAY (day), then I get the money. I've been trying this question for over 2 years now...havn't got the right answer. And now he offers me money.
I refuse to disclose any information about him <!--emo&:p--><img src='http://www.unknownworlds.com/forums/html/emoticons/tounge.gif' border='0' style='vertical-align:middle' alt='tounge.gif' /><!--endemo-->
So anyway, here is the question:
How can you measure speed without using time or distance?
Answers are not:
Speed the drug?
"there is no answer"
"speedometer"
or any obvious answers.
Please be as detailed as possible. And use big words <!--emo&:D--><img src='http://www.unknownworlds.com/forums/html/emoticons/biggrin-fix.gif' border='0' style='vertical-align:middle' alt='biggrin-fix.gif' /><!--endemo-->
I need the answer VERY soon...cause I need any money I can get.
I'll give anybody that answers...my love and appreciation.
The answer apparantly has to do with physics, and can easily be applied to astronomy. I need the answer ASAP.
/edit: It would also be helpful to PM me AND post here. But it isn't necessary...
I refuse to disclose any information about him <!--emo&:p--><img src='http://www.unknownworlds.com/forums/html/emoticons/tounge.gif' border='0' style='vertical-align:middle' alt='tounge.gif' /><!--endemo-->
So anyway, here is the question:
How can you measure speed without using time or distance?
Answers are not:
Speed the drug?
"there is no answer"
"speedometer"
or any obvious answers.
Please be as detailed as possible. And use big words <!--emo&:D--><img src='http://www.unknownworlds.com/forums/html/emoticons/biggrin-fix.gif' border='0' style='vertical-align:middle' alt='biggrin-fix.gif' /><!--endemo-->
I need the answer VERY soon...cause I need any money I can get.
I'll give anybody that answers...my love and appreciation.
The answer apparantly has to do with physics, and can easily be applied to astronomy. I need the answer ASAP.
/edit: It would also be helpful to PM me AND post here. But it isn't necessary...
Comments
E= 1/2 * m * v²
v= [root](2*E/m)
unless your talking about force/mass which is velocity which is speed with direction. theres plenty of ways to find speed without using distance and time directly in the problem, but they are included in the equation somewhere.
unless you go the calculus way and use functions, but those are still using distance and time.
and obst, kinetic energy is .5mass(velocity^2). and any kenetic energy was potential energy at one time, (mass X gravity X height) and kinetic energy can also be seen as work, (force X distance)
momentum = mass * velocity
edit: now that I think about it, this is really just the derivative of kinetic energy with respect to v
1. You must know the actual MASS of the object....
THEN from measuring the actual mass of it, you can solve for its velocity using a bunch of cool equations, Im not sure what equations, but i do know that as you approach the speed of light, mass becomes infinite, or 0, i cant remember... but i do know its predictable, and it will follow a curve... so solving for V would not be too difficult once you find the value on the curve for the selected mass.... Really all you need is "stopped" mass, and mass at speed, and you can solve for the velocity it is travelling based on the fact that mass varies with speed based on E=MC^2 and what not......
Ill leave somenoe else to clean this up... ive actually been doing physics homework for 3 hours so far... and my brain is beginning to rot
~Jason
Edit: It's all based on the doppler effect, though I can't find a specific equation right now.
btw could you give us the EXACT question? It might have something to do with the kind of the question.
Work determines the displacement due to mass (force over distance) and power brings the time element in.
Other than that.. i don't know.
i do believe even the frequency one involves time and distance. if im right the frequency is refering to a distance/time function where the tangent of the line at any given place would be the speed. the higher the frequency the higher the tangent, therefore the higher the speed.
I assume that you mean to determine speed without measuring distance or time directly.
The only way I can think of doing this is to measure the frequency of a reflected beam from two different points.
You would get the speed directly towards or away from those 2 points, then apply some trigonometry, you can get the actual speed.
That's my best guess anyway.
Assuming we're measuring the moon's speed. 2 points on the earth's surface as far apart as possible, they each get a speed towards or away from that point. Using trig you then calculate the actual speed of the moon.
edit:
He says "Astronomy" in his first post. So while a lot of the stuff posted is good ideas, it wouldn't really work applied to planetary or stellar sized objects.
Diazo
Triangulation is when you look at an object from one place (in astronomy, where Earth is during summer solstice), then look at the same object from the other place (where Earth would be during winter solstice).
Sorry, that wasn't too helpful, meh. It might help.
Edit: If it has to do with astronomy, I think the people suggesting doppler shift equations are on the right track.
This would be what I would say. I don't know if you have to put in speed or distance of the object in order to make this work, but if you just have to know the wavelength of the object with and without redshift, then there is your answer.
This would be what I would say. I don't know if you have to put in speed or distance of the object in order to make this work, but if you just have to know the wavelength of the object with and without redshift, then there is your answer. <!--QuoteEnd--></td></tr></table><div class='postcolor'><!--QuoteEEnd-->
There is no need to measure time when measuring red shift to determine the velocity. If you know the wavelength of an object at rest (relative to you), and can identify it when red shifted (or blue shifted if it happens to be coming at you), then you can determin its velocity relative to yours.
How much of that $400 do we get?
IE: You know is coming towards you at 20k/s, but how fast is it travelling towards your left or right?
Using the doppler effect, I think that you need to use two points or reference to get the object's actual speed, just not it's speed towards or away from you.
Diazo
PS: Just realised that two points is only enough for speed in a plane, such as a ground based object like a car, or a star's speed in the galactic plane. You'd have to add a 3rd point for speed in a 3D enviroment.
IE: You know is coming towards you at 20k/s, but how fast is it travelling towards your left or right?
Using the doppler effect, I think that you need to use two points or reference to get the object's actual speed, just not it's speed towards or away from you.
Diazo
PS: Just realised that two points is only enough for speed in a plane, such as a ground based object like a car, or a star's speed in the galactic plane. You'd have to add a 3rd point for speed in a 3D enviroment. <!--QuoteEnd--></td></tr></table><div class='postcolor'><!--QuoteEEnd-->
Actually this is my fault, since I wrongly used the term velocity (sorta, velocity is speed + direction, and since you can tell the object's direction somewhat...), speed is a scalar, it doesn't specify direction.
So in other words, he doesn't need to know what direction it is going.
distance = | start pos - end pos |
time = | start time - end time |
speed = | start pos - end pos | / | start time - end time |
speed is the absolute value of the starting position minus the final position divided by the abolute value of the ending time subtracted from the starting time
edit: einstein says:
measure the length of an object at rest relative to your reference frame, as the object approaches the speed of light, the length of the object will approach zero. (length being the dimension parallel to the direction of motion, the speed of light being the speed of light in a vaccum AKA "c") all you need is a ruler. (with very, very accurate labels)
edit2: <a href='http://en.wikipedia.org/wiki/Length_contraction' target='_blank'>http://en.wikipedia.org/wiki/Length_contraction</a>
None of these were right...no money for me <!--emo&:(--><img src='http://www.unknownworlds.com/forums/html/emoticons/sad-fix.gif' border='0' style='vertical-align:middle' alt='sad-fix.gif' /><!--endemo-->
None of these were right...no money for me <!--emo&:(--><img src='http://www.unknownworlds.com/forums/html/emoticons/sad-fix.gif' border='0' style='vertical-align:middle' alt='sad-fix.gif' /><!--endemo--> <!--QuoteEnd--> </td></tr></table><div class='postcolor'> <!--QuoteEEnd-->
so... what was the answer?
And yeah I can't hit him either. He lives in FL, and I live in MI. He's gonna send me the money (well he would have, anyway).
Your dad is a ****ing liar.