mm-3449 === Subject: Re: NUMBER I dunno, at least in the canonical representation of the real numbers, every number's additive inverse looks similar, except it has an extra appendage on it. Sounds pretty heterosexual to me. > 2+2=8 and a half === Subject: Re: NUMBERS > 2+2=8 and a half I doubt the ability of a number or numbers to have a sexual orientation. Math can do alot but choosing which side of the fence numbers are on is beyond it's scope. What I can tell you is that our friend Ryan appears gay. Not in the homosexual sense though, there would be nothing wrong with that. Ryan is gay in the socially lame and totally unnacceptable sense. It's all semantics anyway. later === Subject: Derivative Problem I need to know the derivative to this equation and the equation to the line that crosses tan to point (0,1) f(x) = 1 / (x+1) The answer i keep getting i know isnt right as you can see or i wouldnt be asking people on here. Bobby === Subject: Re: Derivative Problem I need to know the derivative to this equation and the equation to the line > that crosses tan to point (0,1) f(x) = 1 / (x+1) That's pretty much gibberish, and I suspect as long as you pose problems in this manner, you'll have trouble with them. === Subject: Re: Derivative Problem I think what he wants here is y=1. I need to know the derivative to this equation and the equation to the line > that crosses tan to point (0,1) > That's pretty much gibberish, and I suspect as long as you pose > problems in this manner, you'll have trouble with them. === Subject: Re: Derivative Problem I need to know the derivative to this equation and the equation to the line > that crosses tan to point (0,1) f(x) = 1 / (x+1) The answer i keep getting i know isnt right as you can see or i wouldnt be > asking people on here. Bobby You could use the quotient rule [1], that is (u/v)' = (v*u' - u*v')/(v^2) In your case, f(x) = 1/(x + 1), you can write u = 1 and v = (x + 1). Therefore, we have u' = (1)' = 0 since u is a constant and v' = (x + 1)' = (x)' + (1)' -- Addition rule = 1 + 0 = 1 Thus the derivative of f(x)is going to be f'(x) = ((x + 1)*0 - 1*1)/(x + 1)^2 = -1/(x + 1)^2 HTH, Jean-Marc [1] http://archives.math.utk.edu/visual.calculus/2/quotient_rule.4/index.html === Subject: Re: Derivative Problem I need to know the derivative to this equation and the equation to the line > that crosses tan to point (0,1) f(x) = 1 / (x+1) The answer i keep getting i know isnt right as you can see or i wouldnt be > asking people on here. Bobby -1/(x+1)^2 === Subject: Re: Derivative Problem How did you get that? >> I need to know the derivative to this equation and the equation to the >> line that crosses tan to point (0,1) >> f(x) = 1 / (x+1) >> The answer i keep getting i know isnt right as you can see or i wouldnt >> be asking people on here. >> Bobby -1/(x+1)^2 === Subject: Re: Derivative Problem I need to know the derivative to this equation and the equation to the line > that crosses tan to point (0,1) f(x) = 1 / (x+1) The answer i keep getting i know isnt right as you can see or i wouldnt be > asking people on here. Bobby Show some work so we can check it. Dave === Subject: Re: Derivative Problem Well what i have isnt right but this is as far as i got u need to move everything to the top so: 1(x+1)^-1 and whole numbers = 0 so im at: x^-1 then i mult x*-1 and then take one off of the power so im at -x^-2 for the derivative then plug in the x from the point into that and get 0=m then the y=mx+b plug in 1=0*0+b so b should = 1 so the equation should be y=0x+1 to by tan to the first graph im off somewhere and im sure its something easy but i dont see it yet >> I need to know the derivative to this equation and the equation to the >> line that crosses tan to point (0,1) >> f(x) = 1 / (x+1) >> The answer i keep getting i know isnt right as you can see or i wouldnt >> be asking people on here. >> Bobby > Show some work so we can check it. Dave === Subject: Re: spoileR: 548^2, what is the area sum of 4 constructible polygons. <61mie21676bhjn221pk1o6i102jrljlsrh@4ax.com >spoileR: 548^2, what is the area sum of 4 constructible polygons. world of mathematics weisstein e.., ... Compass and straightedge geometric constructions dating back to Euclid were capable of inscribing regular polygons of 3, 4, 5, 6, 8, 10, 12, 16, 20, 24, 32, 40, 48, 64, ..., sides. However, ever, Gauss showed in 1796 (when he was 19 years old) that a complete list of constructible -gons was given by , 4, 5, 6, 8, 10, 12, 15, 16, 17, 20, 24, 30, 32, 34, 40, 48, 51, 60, 64, ... (Sloane's A003401). A complete enumeration of constructible polygons is given by those with central angles corresponding to so-called trigonometry angles. I get the feeling that there's a decent puzzle somewhere in here, but > it's obscured by really poor wording. The most natural reading of > the sentence quoted above is as follows: Describe four polygons constructible with compass and straightedge, > and whose areas sum to 548^2. You are right. But what I wish is regular n-gons, whose side is 1 and perimeter n and Area order n^2. E.g. S = n1^2+ n2^2 + n3^2 + n4^2. Where perhaps n1 < n2< n3 < n4. are the number of sides of constructible polygons... S = 30.03.04. = 300304. Can you see what I wished? You gave me better insight. which has a trivial solution: Four 274x274 squares. There is a better puzzle which requires setting out. cheers Don McDonald 22.8.06. === Subject: Re: spoileR: 548^2, what is the area sum of 4 constructible polygons. >>spoileR: 548^2, what is the area sum of 4 constructible polygons. >world of mathematics weisstein e.., >... >Compass and straightedge geometric constructions dating back to Euclid >were capable of inscribing regular polygons of 3, 4, 5, 6, 8, 10, 12, >16, 20, 24, 32, 40, 48, 64, ..., sides. However, ever, Gauss showed in >1796 (when he was 19 years old) that a complete list of constructible >-gons was given by , 4, 5, 6, 8, 10, 12, 15, 16, 17, 20, 24, 30, 32, ^ I assume there's a 3 missing here. >34, 40, 48, 51, 60, 64, ... (Sloane's A003401). A complete enumeration >of constructible polygons is given by those with central angles >corresponding to so-called trigonometry angles. >> I get the feeling that there's a decent puzzle somewhere in here, but >> it's obscured by really poor wording. The most natural reading of >> the sentence quoted above is as follows: >> Describe four polygons constructible with compass and straightedge, >> and whose areas sum to 548^2. You are right. But what I wish is regular n-gons, whose side is 1 and >perimeter n and Area order n^2. What on earth does area order n^2 mean? A regular 4-gon with side 1 and perimeter 4 has area 1. A regular 6-gon with side 1 and perimeter 6 has area 3*sqrt(3)/2. (and so forth) >E.g. S = n1^2+ n2^2 + n3^2 + n4^2. >Where perhaps n1 < n2< n3 < n4. >are the number of sides of constructible polygons... If that's what you mean, then say it that way, rather than that confusing area order stuff: Find four distinct numbers whose squares sum to 548^2, such that for each number n, a regular n-gon is constructible using only compass and straightedge. >S = 30.03.04. >= 300304. A brute-force search: 0001 DATA 3,4,5,6,8,10,12,15,16,17,20,24,30,32,34,40,48,51,60,64,68,80 0002 DATA 85,96,102,120,128,136,160,170,192,204,240,255,256,257,272 0003 DATA 320,340,384,408,480,510,512,514,544,-1 0004 DIM A[548] 0005 WHILE 1 0006 READ DATA I 0007 IF I>549 THEN BREAK 0008 LET A[I]=1 0009 WEND 0010 FOR I=3 TO 545 0015 IF A[I]=0 OR I^2+(I+1)^2+(I+2)^2+(I+3)^2>548^2 THEN GOTO 0090 0020 FOR J=I+1 TO 546 0025 IF A[J]=0 OR I^2+J^2+(J+1)^2+(J+2)^2>548^2 THEN GOTO 0080 0030 FOR K=J+1 TO 547 0035 IF A[K]=0 OR I^2+J^2+K^2+(K+1)^2>548^2 THEN GOTO 0070 0040 FOR L=K+1 TO 548 0045 IF A[L]=0 OR I^2+J^2+K^2+L^2>548^2 THEN GOTO 0060 0050 IF I^2+J^2+K^2+L^2=548^2 THEN PRINT I,J,K,L 0060 NEXT L 0070 NEXT K 0080 NEXT J 0090 NEXT I quickly turns up the following: 4 16 64 544 30 102 170 510 === Subject: Re: spoileR: 548^2, what is the area sum of 4 constructible polygons. <61mie21676bhjn221pk1o6i102jrljlsrh@4ax.com> You found the solution that had inspired me to write this puzzle, and another solution. Derived from my weird pythagorean clock puzzle. SPOILER SPOILER SPOILER 30.03.04 - 1.04.04 = 289.900 = 170^2*10 +30^2. =(17*2*5)^2 * (3^2+1) + 30^2. = 548^2- (6*17)^2. you complete it. 548^2 = 102^2 +170^2 + 510^2 + 30^2. > weird pythagorean clock. AND recent DATES. > What on earth does area order n^2 mean? E.g. S = n1^2+ n2^2 + n3^2 + n4^2. >Where perhaps n1 < n2< n3 < n4. >are the number of sides of constructible polygons... If that's what you mean, then say it that way, rather than that > confusing area order stuff: Find four distinct numbers whose squares sum to 548^2, such > that for each number n, a regular n-gon is constructible > using only compass and straightedge. S = 30.03.04. >= 300304. A brute-force search: 0001 DATA 3,4,5,6,8,10,12,15,16,17,20,24,30,32,34,40,48,51,60,64,68,80 > 0002 DATA 85,96,102,120,128,136,160,170,192,204,240,255,256,257,272 > 0003 DATA 320,340,384,408,480,510,512,514,544,-1 > 0004 DIM A[548] > 0005 WHILE 1 > 0006 READ DATA I > 0007 IF I>549 THEN BREAK > 0008 LET A[I]=1 > 0009 WEND > 0010 FOR I=3 TO 545 > 0015 IF A[I]=0 OR I^2+(I+1)^2+(I+2)^2+(I+3)^2>548^2 THEN GOTO 0090 > 0020 FOR J=I+1 TO 546 > 0025 IF A[J]=0 OR I^2+J^2+(J+1)^2+(J+2)^2>548^2 THEN GOTO 0080 > 0030 FOR K=J+1 TO 547 > 0035 IF A[K]=0 OR I^2+J^2+K^2+(K+1)^2>548^2 THEN GOTO 0070 > 0040 FOR L=K+1 TO 548 > 0045 IF A[L]=0 OR I^2+J^2+K^2+L^2>548^2 THEN GOTO 0060 > 0050 IF I^2+J^2+K^2+L^2=548^2 THEN PRINT I,J,K,L > 0060 NEXT L > 0070 NEXT K > 0080 NEXT J > 0090 NEXT I quickly turns up the following: 4 16 64 544 > 30 102 170 510 don.mcdonald 23.8.06. === Subject: Re: spoileR: 548^2, what is the area sum of 4 constructible polygons. <61mie21676bhjn221pk1o6i102jrljlsrh@4ax.com> link .. 30.03.04 - 1.04.04 > = 289.900 > = 170^2*10 +30^2. =(17*2*5)^2 * (3^2+1) + 30^2. = 548^2- (6*17)^2. > you complete it. > 548^2 = 102^2 +170^2 + 510^2 + 30^2. > What on earth does area order n^2 mean? > perhaps-- not sure-- something like.. magnitude approximately equals a constant times the second power of n, respectively.. e.g. a polygon approx. perimeter squared over pi ??? A = pi* r*r. > If that's what you mean, then say it that way, rather than that > confusing area order stuff: Find four distinct numbers whose squares sum to 548^2, such > that for each number n, a regular n-gon is constructible > using only compass and straightedge. basic program looks ok.. ..> quickly turns up the following: 4 16 64 544 > 30 102 170 510 don.mcdonald 23.8.06. === Subject: Re: spoileR: 548^2, what is the area sum of 4 constructible polygons. >> What on earth does area order n^2 mean? >perhaps-- not sure-- something like.. This are not good phrases to be using about a puzzle intended to have an exact solution. >magnitude approximately approximately is not a good word to be using, either. >equals a constant times the second power of n, >respectively.. >e.g. a polygon approx. perimeter squared over pi ??? A = pi* r*r. This appears to be true, though (1) it requires showing that r is approximately linear with n (a non-trivial task) and (2) it still evokes far too much confusion to use it as a description, rather than just using the square of a number with such-and-such property. http://www.mathwords.com/a/area_regular_polygon.htm Consider the circle approximated by a regular n-gon with unit sides. This is ambiguous; three good candidates come to mind: 1) Inscribed circle; r = distance from center of polygon to the middle of one of its sides 2) Circumscribed circle; r = distance from center of polygon to one of its vertices 3) Circle with same center and area as the polygon; r = somewhere between the values noted above For any finite n, the area of the polygon is n/4 * cot(pi/n). n -> infinity pi/n -> 0 cot(pi/n) -> infinity cot(pi/n)/n -> 1/pi I have no proof of that last result, but a brute-force scan strongly suggests it: 0010 PRECISION 14 0015 LET PI=3.1415926535 0020 FOR N=100 TO 1000000 STEP 100 0030 PRINT @(0),N,@(10),1/TAN(PI/N),@(30),1/(N*TAN(PI/N)) 0050 NEXT N (last ten lines of output) 999100 318023.40729426 .31830988619183 999200 318055.23828288 .31830988619183 999300 318087.0692715 .31830988619183 999400 318118.90026012 .31830988619184 999500 318150.73124874 .31830988619183 999600 318182.56223736 .31830988619183 999700 318214.39322599 .31830988619184 999800 318246.22421461 .31830988619184 999900 318278.05520323 .31830988619184 1000000 318309.88619184 .31830988619184 So, as n increases, the radius of the circle-with-same-area approaches n/pi, thus the area of that circle approaches pi*(n/pi)^2 = (n^2)/pi. The math would be somewhat different for the inscribed and circumscribed circle, but they approach equality to the circle-with-same-area as n increases, so their limits are the same as the limits of the circle-with-same-area. === Subject: Can I do this? Change a vector basis with projection? change a vector's basis without having to find the inverse of the new Basis's matrix. Tell me if this is logical, and if so, is there a name for this method? (Vectors are denoted with a []) This example is in 2D for simplicity. Let B=[B1][B2] = the new orthonormal basis [S] = the vector whose basis we want to change [S'] = the linear combination of B to make [S] S can be expressed as the the sum of its projections onto B: S=Proj[S]->[B1] + Proj[S]->[B2] S=([S] . [B1]) * [B1] + ([S] . [B2]) * [B2] (the projection formula, with ||B1||=||B2||=1 since B is orthonormal) here is our linear combination. S' = ([S].[B1] , [S].[B2]) S' is expressed in the new basis. Is this logical? What is this method called? === Subject: Linear Algebra - how to prepare for class? I'm taking a linear algebra class in 3 weeks. How can I prepare for this class? What areas should I study/review so I'm ready to start this class at full speed? I've had math up through Calculus 4 (vectors) === Subject: Re: Linear Algebra - how to prepare for class? Check out; http://math.about.com/gi/dynamic/offsite.htm?zi=1/XJ&sdn=math&zu=http%3A%2F% 2Fwww.numbertheory.org%2Fbook%2F WDA end > I'm taking a linear algebra class in 3 weeks. How can I prepare for this > class? What areas should I study/review so I'm ready to start this class > at full speed? I've had math up through Calculus 4 (vectors) > ---------------------------------------------------------------------------- ---- It has removed 205 spam emails to date. Paying users do not have this message in their emails. === Subject: Re: Linear Algebra - how to prepare for class? Review matrices, determinants, cross products, simultaneous equations and basically anything having to do with vectors. It wouldn't hurt to get a Schaum's outline now and start learning on your own if you're really interested. btw...calculus won't come up. -Doc > I'm taking a linear algebra class in 3 weeks. How can I prepare for this > class? What areas should I study/review so I'm ready to start this class at > full speed? I've had math up through Calculus 4 (vectors) === Subject: Re: Linear Algebra - how to prepare for class? I just finished calc 4, so I'm good with vectors and cross products. That will help. I just bought the book, and got the syllabus. I think I'll spend the next few weeks before the class getting as far ahead as I can get. This instructor gives tests from hell, but this is the only time the class is > Review matrices, determinants, cross products, simultaneous equations > and basically anything having to do with vectors. It wouldn't hurt to > get a Schaum's outline now and start learning on your own if you're > really interested. btw...calculus won't come up. > -Doc > I'm taking a linear algebra class in 3 weeks. How can I prepare for this >> class? What areas should I study/review so I'm ready to start this class >> at >> full speed? I've had math up through Calculus 4 (vectors) > === Subject: Re: Linear Algebra - how to prepare for class? > I'm taking a linear algebra class in 3 weeks. How can I prepare for this > class? What areas should I study/review so I'm ready to start this class at > full speed? I've had math up through Calculus 4 (vectors) Spend most of your time reviewing vectors. When I had it, I don't remember doing a lot of calculus. Dave === Subject: Re: Linear Algebra - how to prepare for class? >> I'm taking a linear algebra class in 3 weeks. How can I prepare for this >> class? What areas should I study/review so I'm ready to start this class >> at full speed? I've had math up through Calculus 4 (vectors) > Spend most of your time reviewing vectors. When I had it, I don't remember > doing a lot of calculus. Dave Vectors for linear algebra? They only require Calc 2, which does not yet get into vectors. Calc 4 was vector hell, and I barely survived it, but here Calc 1 and 2 only takes you through derivatives and integration for the most part. === Subject: Wrong forum for discussion of the Fields Medal awards? It's only the biggest award in the world of mathematics, yet nothing here about the Fields Medal awards? I'm only a small-time math fan, turning here to hear more about this year's winners. Nothing? -Tom. === Subject: Re: Wrong forum for discussion of the Fields Medal awards? > It's only the biggest award in the world of mathematics, yet nothing > here about the Fields Medal awards? > I'm only a small-time math fan, turning here to hear more about this > year's winners. Nothing? The serious postings about this are in sci.math. -- === Subject: Re: seek freeware for basic geometry On 27 May 2006 02:20:50 -0700, Rufi_Dukes Why would such program - if it exists - have 0 value to you? -Tom. >does anyone here know of a freeware proggy on a par with xyzalgebra, >but for geometry? >that is, a freeware prog that assumes no prior geometry and takes you >through the basics in a graduated, structured way? thx, >rufus === Subject: Linear Algebra Subspace problem Hello! Who could help me with the following: Given a 5-dimensional vectorspace (e.g. K^5, K algebraically closed field), I am looking for all 4-dimensional subspaces. How could I find and describe these (using basis notation, matrices etc...) ? Phil. === Subject: Re: Linear Algebra Subspace problem > Hello! Who could help me with the following: Given a 5-dimensional vectorspace (e.g. K^5, K algebraically closed > field), I am looking for all 4-dimensional subspaces. How could I find and describe these (using basis notation, matrices > etc...) ? Phil. In K^5 the easiest way to describe the 4-dimensional subspaces is consider for each v in K^5 {0} the hyperplanes H_v = { x in K^5 : v_1 x_1 + ... + v_5 x_5 = 0 }. Note that H_v = H_w iff v = k w for some k in K {0}. If you want a unique representation, take v_i = 1 for the first nonzero component of v. Mate === Subject: Re: Linear Algebra Subspace problem > Who could help me with the following: Given a 5-dimensional vectorspace (e.g. K^5, K algebraically closed > field), I am looking for all 4-dimensional subspaces. How could I find and describe these (using basis notation, matrices > etc...) ? Hmmm- I would start by looking at the possible vectors that would form the basis for the corresponding 1-dimensional null space. If you can divide these into classes somehow, that would give a characterization of the possible 4-dimensional subspaces. For example - all the possible 2-dimensional subspaces of R^2 are the planes through the origin - as characterized by their corresponding null spaces (the normal vector for the given plane). Or am I missing something here - it's been a while... cheers- Eric === Subject: Trig problem Could anyone help with the following? Show that [ 4 ( 1 - cos(2t) ) ] / [ sin^3(3t) - sin^3(t) - 6 * sin^2(t) * sin(3t) * cos(2t) ] Can be expressed as 1 / ( cos^3(2t) * sin(t) ) Where * is multuiply and ^ is raise-to-power, so sin^3(3t) in the cube of the sine of 3t === Subject: Re: Trig problem > Could anyone help with the following? [ 4 ( 1 - cos(2t) ) ] / [ sin^3(3t) - sin^3(t) - 6 * sin^2(t) * sin(3t) > * cos(2t) ] Can be expressed as 1 / ( cos^3(2t) * sin(t) ) > Off the cuff first guess is to use sin 3t = sin 2t * sin t + cos 2t * cos t. Which does you the favor of reducing the arguments t, 2t, 3t to t, 2t at the cost of much belabored algebraic labour. === Subject: Re: Nominate me for Abel Prize please > Is the Abel prize not for lifetime achievement rather than > mathematical bad taste? Yes, but he doesn't really want the prize; he just wants the chance to decline it. Bart -- The man without a .sig === Subject: counting Does anyone know of any good websites that explain counting strategies, === Subject: Re: counting > Does anyone know of any good websites that explain counting strategies, Xn= X(n-1) +1. For example 1 2 3 4 5 6 7....etc...... Alternatively you can cheat and use your fingers. === Subject: Re: counting Bazzer Smith, you are a useless tool. Nonetheless, I thank you for the counting problem that you find so challenging that you have alternatively resorted to cheating. Does anyone know of any good websites that explain counting strategies, Xn= X(n-1) +1. > For example 1 2 3 4 5 6 7....etc...... Alternatively you can cheat and use your fingers. > === Subject: Re: counting Nothing wrong with my post the fault appear to be with your badly drafted original :O) > Bazzer Smith, you are a useless tool. Nonetheless, I thank you for the > counting problem that you find so challenging that you have alternatively > resorted to cheating. > Does anyone know of any good websites that explain counting strategies, >> Xn= X(n-1) +1. >> For example 1 2 3 4 5 6 7....etc...... >> Alternatively you can cheat and use your fingers. === Subject: Re: counting What exactly are you referring to be badly drafted original? You are being completely unreasonable and still again ... being a tool. > Nothing wrong with my post the fault appear to be with your badly > drafted original :O) > Bazzer Smith, you are a useless tool. Nonetheless, I thank you for the > counting problem that you find so challenging that you have alternatively > resorted to cheating. > Does anyone know of any good websites that explain counting strategies, >> Xn= X(n-1) +1. >> For example 1 2 3 4 5 6 7....etc...... >> Alternatively you can cheat and use your fingers. > > === Subject: Re: counting > Does anyone know of any good websites that explain counting strategies, Google for combinatorics. --- Christopher Heckman === Subject: Re: counting had a favorite website or perhaps some favorite books they wanted to recommend. Does anyone know of any good websites that explain counting strategies, Google for combinatorics. --- Christopher Heckman > === Subject: Question HELP PLEASE Using the Numbers 4 3 2 1 Come up with the ANSWER of 27 and 29. M.9fTtLaNgE === Subject: Re: Question HELP PLEASE Here's the Answer to the 27 3^4=81 Divided by (2+1) +27 God Bless all who answered I still need 29 === Subject: Re: Question HELP PLEASE REPOST > Here's the Answer to the 27 3^4=81 Divided by (2+1) =27 God Bless all who answered I still need 29 === Subject: Re: Question HELP PLEASE >Using the Numbers 4 3 2 1 Come up with the ANSWER of 27 and 29. >M.9fTtLaNgE > 27 = 3^3 29 = 3^3 + 2 27 = 2*(4 + 3 + 2 + 1) + 4 + 3 29 = 1+1+1+1+1+1+1+1+1+1+1+1+1+1+1+1+1+1+1+1+1+1+1+1+1+1+1+1+1 etc. === Subject: Re: Question HELP PLEASE > Using the Numbers 4 3 2 1 Come up with the ANSWER of 27 and 29. > M.9fTtLaNgE 27 = 4(4+3) -2 + 1 29 = 3^3 + 4 + 1 - (2 + 1) Ray Steiner === Subject: Re: Question HELP PLEASE You can Only use the Numbers Once, and you can't Use Double Digits. Such as 43 21 12 32 34 come up with the answers from 1-30 ie 4X3 ( 12) Divided BY 2 (6) + 1 = 7 ie 4+1 (5) X3 15 X 2 = 30 ie 4-3 (1) -1+2 = 2 === Subject: Re: Question HELP PLEASE |> Using the Numbers 4 3 2 1 Come up with the ANSWER of 27 and 29. | 27 = 4(4+3) -2 + 1 | 29 = 3^3 + 4 + 1 - (2 + 1) I'm pretty sure the point is to use just one number each, otherwise, 27 = 1 + 1 + 1 + 1 + 1 + ... + 1 (much too easy). __________Gerard S. === Subject: Re: A fun problem to calculate I worked out the energy involved at the same as that in a 1 megatonne nuclear weapon. The earth has survived many of those!!!! >I discovered this interesting question a few months back. It is > relatively easy to solve but the scenario relies completely on chance. If a meteorite the size of a golf ball strikes earth at 1/2 the speed > of light, will we survive? It is relatively to calculate the average density using data from NASA > and Wikipedia. The question the variable that will really get you > thinking is supposing the meteorite is solid or supposing that the > meteorite is molten or somewhere in between. The outcome would also rely on where the meteorite struck. Obviously if > it hit in one of Earths oceans, the sudden deceleration would likely > fracture it into a million harmless pieces. (referencing Discovery > Channel's Mythbusters episode involving shooting high powered rifles > into a pool) Food for thought. -Steven Biars > === Subject: Re: A fun problem to calculate That question is not relevant, the question states one does. > Would a meteorite the size of a golf ball moving at half the speed of > light completely sublimate in the atmosphere before reaching the Earth's > surface? end >I discovered this interesting question a few months back. It is >> relatively easy to solve but the scenario relies completely on chance. >> If a meteorite the size of a golf ball strikes earth at 1/2 the speed >> of light, will we survive? >> It is relatively to calculate the average density using data from NASA >> and Wikipedia. The question the variable that will really get you >> thinking is supposing the meteorite is solid or supposing that the >> meteorite is molten or somewhere in between. >> The outcome would also rely on where the meteorite struck. Obviously if >> it hit in one of Earths oceans, the sudden deceleration would likely >> fracture it into a million harmless pieces. (referencing Discovery >> Channel's Mythbusters episode involving shooting high powered rifles >> into a pool) >> Food for thought. >> -Steven Biars ----------------------------------------------------------------------------- --- > It has removed 23 spam emails to date. > Paying users do not have this message in their emails.