Challenge Definition and 942 Threads

A satellite is orbiting the Earth at an rate of 96 minutes. The radius of the Earth and the mass is known. How do I calculate how high above Earth the satellite is orbiting? I tried to use formula a= 4*(3.14^2)*(r+6380)/t But I don't have the acceleration, and If I would use Newtons law of...

Second one: Protons are projected at an angle of 300 with an initial speed, given by V0=8.2*105 m/s, in a region of an electric field E=-390j N/C, is present. The proton is to hit a point 1.27 mm in the pos-x direction from the launch point. Find (a) the two porjections angles (theta) that...

A ladder of length 2a and weight W, with its centre of gravity 3/8 of the way up it, stands on a smooth horizontal plane resting against a smooth vertical wall, and the middle point is tied to a point in the wall by a horizontal rope of length b. Find the tension in the rope.

Well, my physics teacher loves to make his problems hard, so he makes the physics portion of the problem med difficulty but he makes it so you have to solve with more than 1 unknown present. With big problems on forces I get lost in the algebra so.. I'm trying to improve my algebra skills. If...

http://chinkchinatown.com/extra.jpg Ok as you can see the initial velocity is 6.425 m/s^2 and it is about .871m off the ground and about 3.25 m from the target. We have to find the angle at which to place the gun that shoots this ball to hit the target. This target it only like 1 inch at...

[SOLVED] The photophone challenge Hi everybody, (reply: "Hi, Dr. Nick" even though my name is not Nick) I saw this design contest near where I live where participants had to design and build an apparatus that would transfer an audible vocal message over a distance of @ least 20m, by using...

Here is a file i created of a problem I was asked if see if you have what it takes:

Solve for x. 2^{x+1} + 2^x = 9 lg(x-8) + lg(\frac{9}{2}) = 1+ lg(\frac{x}{4}) I can't get the answers

Picture a room (a rectangular prism) that is 10 feet long x 4 feet wide x 3 feet high. Now, in the middle of the 4 foot wall, .3 feet down from the top, there is a clock. On the opposite wall, .3 foot from the bottom, there is an outlet. So... I want the shortest length for the...

For a charged particle the Velocity Vector is in the i direction and the magnetic field is in the -k direction, prove using Newton's Second Law that the trajectory of this charged particle must be circular. (Hint F=q(V x B) this is the magnetic Force equation.)

I took a trip in August. I am curious to see if anyone can figure out the places where I took these digital pictures. Now if you figure Janitor as an international playboy jetsetter, these pictures could have been taken anywhere in the world. Otherwise, you can safely assume they were accessible...

Alright, to counter-act GENIERE's thread about being able to find a flip-flop about every stance Kerry's ever taken, I challenge you Bush fans to come up with stances that Bush's taken, and I'll see if I can't find an instance where he's flip-floped about his stance on it, or outright lied about...

To find an issue of some importance that Kerry has not been “for and against”. You provide the “flip”, I’ll provide the “flop”. For instance re: "war on terror", you provide (include reference): ‘…It’s basically a manhunt…’ I’ll provide: ‘…This war isn’t just a manhunt…’...

Could one of you scientists out there help me? A friend of mine is reading a book called 'Uncommon Dissent', which she says makes a serious claim for doubting the basic tenets of the theory of natural selection. I suspect that this book and its claims might be flat-earth stuff, easily debunked...

Hey everyone, I am trying to solve this challenge question on finding the inverse laplace transform of f(s)=\frac{5se^{-3s} - e^{-3s}}{s^{2}-4s+17} Heres my reasoning: I feel that I should split up that denominator into two linear factors, however its that odd 17 that is very troublesome...

blind man+ new prob :) 2 blind man each holding 3 pairs of newly bought socks of different colours (red, green ,blue). They bumped into each other and the socks fell to the ground. Find a way to help they get their socks back. as in a pair of each colour. :smile:

i recently sat a national mathematics competition and came across this question, which i thought was pretty good. I am posting it here to see how long it takes everybody to figure out. (the question has been wordedly differently) The sum of three children's ages is 23. The product of their...

This problem should be very difficult for those of you inexperienced with geometry, yet anyone who has taken geometry and trigonometry is capable of solving this problem. Feel free to post the answer/ discuss, hopefully more of the latter. There is a circle of grass with the radius R. We...

Once again, send answers with explanation through private message or email GeneralChemsitryTutor@hotmail.com. We are playing baseball on an airless planet. A fly ball is hit directly towards an outfielder. The fielder can detect the changing angle that the ball makes with the horizon, but...

can you give the next two rows? 1 11 21 1211 111221 312211 13112221 1113213211 31131211131221 ------------------- -------------------

i think that most of you people are smart enough to find the first part, a piece of cake. WELL, HOLD ON! that was just the warming up session. this one is the real cracker. let's see how good are you at this one. You're sitting in your office, when your boss walks in...

I assume that most of you have played poker at some time so here is a poker question. When dealt only three cards with three's being wild, are the odds of getting three of a kind higher or lower than getting a straight flush? Keep in mind you can only use the three cards that are dealt to you...

A math teacher gave this problem years ago when I was in High School. We had just finished a couple of hours of calculus, and there were only about three minutes left of the lesson. He gave us thirty seconds to give the correct answer, give yourself the same time, or fail. A man rides a...

Silly challenge to God Some people use this as proof that God doesn't exist: They say, "God strike me dead in five minutes." Five minutes pass and God doesn't strike them dead. This is so silly to me that it hardly even deserves a response. But I will give one to show how silly it is. Let's say...

Okay I've got a fields exam coming up so like a good boy I've been practising with past papers :wink: but there is this one question that is driving me batty :confused: a) Consider a long cylindrical co-axial capacitor with inner conductor radius a, outer conductor radius b, and a...

show that the polynomial g(x)=(x^2 -5) (x^2-41)(x^2-205) has a solution modulo any integer n∈ℕ.

How do i do a Multiple Alignment with 4000 sequences. offline version of ClustalW hangs online version accepts only 500 sequences What is the maximum number of sequences that can be given to CluatalW ? Any other gud softw . PLease let me know ...

as we read these various philosophy forums we see many posts citing various source material and what these writers believe. these are used as an authority for what the poster wishes to substaniate. how many of us believe in freewill (please no posts showing that we do or don't have one) and...

So has anyone got this little toy? http://www.levitron.com/ I bought it a while ago, played with it for half an hour and gave up. It was too hard, at least for me, to get it adjusted correctly and everything. But tonight I found it again and this time it works pretty well. Still can't get it...

Thought you might want a quick blast on this submarine shoot-em-up http://www.netaddition.com/game/ I'm still fixing the high score table at the moment.

http://www.bfro.net/news/challenge/home.asp

Ok, is there any solid, liquid, or gas that becomes heavier as it gets warmer and lighter as it gets colder? Like a reverse lava lamp. The little physics I know says no but I Know VERY little, you know? CJ

Newton's laws? there is an athlete climbing a rope in gym class. he gets to a point halfway up the rope and is stationary. someone puts a bag of sand that is equal in weight to the athlete. they are both static and then the athlete starts to climb the rope, slowing and speeding up at random...

Ram has a rectangular piece of card board out of which he clipped away the largest possible square and was left with a piece similar in shape to the original piece. The area of the piece remaining with Ram forms approx what percent of the original piece

A new claim has appeared in physics. It is claimed that there is a largest possible force, namely c^4/4G or 3 x 10^43 Newton. (The claim is made in the paper http://xxx.lanl.gov/abs/physics/0309118 ) All my friends and acquantances have first said "wrong!" but then failed to produce a...

Would you accept to be chosen to perform the experiment of the quantum suicide?

http://www.bbc.co.uk/science/humanbody/body/interactives/senseschallenge/

I challenge you to name at least one area of physics that the work of Einstein did not somehow affect. If you take this challenge, you, like your pathetic parents, are destined for failure. eNtRopY

I wonder if you could scale this experiment up with a human it could be fun, mind you I am not convinced that the pioneering little frog was alive for very long, if you watch the movie it also seems that only one side of its body works but maybe its just confused or enjoying itself :/ see...

Who will be the first to prove that (with one exception) the sum of any Prime Pair is always divisible by twelve?

Given - 1) Twin earth-sized planets rotate about each other in a solar system. 2) The plane of their mutual orbit is the same plane in which they rotate about their star 3) Their star provides (on average) the same amount of energy as our sun Questions - 1) What is the size and nature of...

(a) When there is a phase-to-neutral fault on a transmission line, will the existence of the neutral wire increase or decrease the magnetic field under the transmission line? Why? (b) Assuming that the whole space consists of an upper half space with soil resistivity r1 and a lower half...