Stuck Definition and 836 Threads

I decided last semester to change my undergrad major to physics, the problem is, due to financial constrains (read: transfer students get no financial aid) I am kinda stuck in a liberal arts college with an underfunded physics department, actually the sciences in general are all underfunded if...

1. ∫(√4x² + 9)/x4 using u = atanθ x = 3/2tanθ dx = 3/2sec²θ I plugged x in and am stuck on simplifying 2. ∫x²/√25 - x²) u = asinθ x = 5sinθ dx = 5cosθ Again, plugged x into original equation...

Homework Statement Evaluate the indefinite integral. Homework Equations I tried to use substitution. The Attempt at a Solution I'm not so good with using the LaTex codes...so I attached a file I made in Word. Thanks in advance!

Homework Statement Homework Equations E=k*Q/r^2 The Attempt at a Solution Ey=E1sin30 + E2sin30 + E3; where E1=E2 (I'm denoting the 2 bottom charges as E1,E2, the negative as E3) Ex=E1cos30 - E2cos30, this cancels. from E=k*Q/r^2 I calculated r^2 to be L^4/4 (don't know if...

Homework Statement At what distance "d", from point "A", the board with the person will slide whereas http://img267.imageshack.us/img267/6139/skkkkkkk.jpg Uploaded with ImageShack.us Homework Equations Weight of board = 50 [kg] Weight of person = 100[kg] Frictional coefficient...

Homework Statement Hello :) I am stuck on this mechanics problem. Any help would be hugely appreciated, because I am just starting with statics. Thank you in advance . A diagram of the problem can be found here :http:////img97.imageshack.us/i/79504950.png A small crane is used in demolition...

Hi, It seems I've forgotten more of my algebra than I thought. I am putting together a spreadsheet to help a few archers determine how to change their point of aim for up- and downhill shots. I would like to reduce/rearrange the following expression so that A and B are not found on the same...

Hi, I am stuck on a specific part of an equation, the equation is as follows; Simplify (x^1/2 +1) (x^2 - x -2) (x -2)^-1 I am basically stuck on the last part (x -2)^-1, how would I go about simplifying this. Help would be appriciated Dominic

sorry if this looks ugly but I couldn't find out how to write out bras and kets on the Latex thing. I have these inner products <f|g> = i<x|(AB - A<B> - <A>B + <A><B>)|x> and <g|f> = -i<x|(BA - B<A> - <B>A + <A><B>)|x> where |x> is some arbitrary ket and A and B do not commute. I'm trying to...

Homework Statement dy/dx=a^2/((x+y)^2) where a is a constant express answer in the form x=f(y) Homework Equations The Attempt at a Solution let u=x+y du/dx=1+dy/dx du/dx=1+(a^2)/(u^2) int(du/(((a^2)/(u^2))+1))=int(a^2 dx) after integration substituting back in for u...

Homework Statement dy/dx=-ylny/x initial conditions y(x=1)=1 express answer in the form f(x,y)=0 Homework Equations The Attempt at a Solution i let u=ln y du/dy=1/y y*du=dy subbing into equation gives int(y/yu du)=-int dx which is equal to int(1/u du)=-int(1/x) dx...

Simple Question (Stuck!) Stuck on my christmas revision questions. Basically here it is below. Homework Statement A ball is thrown vertically with a speed of 17ms-1. A man standing upon a tower 5m above the thrower attempts to catch the ball but fails. He does however catch the ball...

Homework Statement If: (x/l)/(mb+nc-ax) = (y/M)/(nc+la-mb) = (z/n)/(la+mb-nc) Prove: l/x(by+cz-ax)=m/y(cz+ax-by)=n/z(ax+by-cz) The next line in the book says... 1. (ny+mz)/a = 2. (lz+nx)/b = 3. (mx+ly)/c I don't understand how they got to this point... My guess is that they added...

So i have been rapping all the Xmas presents, and needless to say i have lots of the tape stuck to the carpet, i have tried every thing to get it of, hot watter, carpet cleaner, fairy liquid endless picking, now i am a bit brassed off, any tips please.

Homework Statement Define f: [0,\infty) \rightarrow R by f(x) = {0 if x is [0,1] and 1 if x is (1,\infty ) Homework Equations I think if I can show that f is continuous on [0,1] and not continuous on every point of [0,1] then that will suffice. However I have now clue how to go...

Momentum..initial & final & impulse. a 70g tennis ball coming towards you at 25 m/s is hit with a tennis racquet and goes away from u at 30 m/s A) what is the initial momentum of the tennis ball? B) what is the final momentum of the ball ? C) what is the change in momentum of the...

Homework Statement Find the Fourier series of f on the given interval: EDIT: For the result of an, it should be multiplied by \frac{2}{1+n^{2}}. That has been corrected.

Homework Statement dx/dt=x(1-2y) t(0)=0 x(t(0))=1 dy/dt=-y(1-2x), t(0)=0 y(t(0))=2 inerval of integration= [0,40] Homework Equations The Attempt at a Solution i let x=p(t) so t=(p^-1)(x) dy/dx=(∂y/∂(p^-1))∂(p^-1)/∂x dy/dx=(-y(1-2x))/(x(1-2y)) since this equation is...

Homework Statement integrate dy/dx-y=cos(x)-2 Homework Equations The Attempt at a Solution dy/dx-y=cos(x)-2 is in the form dy/dx+p(x)=q(x) take the I.F as e^int(p(x))dx=e^-x multiplying throughout by e^-x d(e^-x)z/dx=-(cos(x)e^-x)-(2e^-x)...

Homework Statement find general solution of dy/dx=xy+x using integrating factor Homework Equations The Attempt at a Solution rearange dy/dx-xy=x take integrating factor as e^int(-x)=e^-(x^2)/2 multiply throughout dy/dx(e^-(x^2)/2)y=(e^-(x^2)/2)x integrate...

Homework Statement I reached the point of sn ≤ M < A and I need to get to |sn - A| ≥ A - M before I can move on and reach my final conclusion. (Don't worry about what I'm trying to prove; just help me on this little step) Homework Equations Not sure because I've never...

Homework Statement A student sits on a rotating stool holding two 2.0 kg objects. When his arms are extended horizontally, the objects are 1.0 m from the axis of rotation, and he rotates with an angular speed of 0.75 rad/s. The moment of inertia of the student plus stool is 3.0 kg·m2 and is...

Homework Statement The only force acting on a 4.3 kg body as it moves along the positive x-axis has an x component Fx = -8x N, where x is in meters. The velocity of the body at x = 1.6 m is 11 m/s. (a) What is the velocity of the body at x = 4.5 m? (b) At what positive value of x will the body...

Im studying Classical Physics and currently covering resonance, one question i got thinking about was why we rattle things that are stuck. Am i right in thinking that we apply a resonance to the natural frequency of the stuck object in order to magnify it's amplitude and hence give our selves...

Homework Statement trying to find the integral curve for ths equation get stuck at trying to integrate 10^-u dy/dx=10^x+yHomework Equations The Attempt at a Solution let u=x+y so dy/dx=10^u du/dx=1+dy/dx =(10^u)-1=du/dx du/dx=(10^u)-1 du/10^u=-dxthanks in advance

Absolutely STUCK on a 2nd derivative! Homework Statement The problem is to find the second derivative of y= [tex]\sqrt{x^2+x-2}[\tex] Homework Equations I know I have to use the Chain Rule and the Quotient Rule. The Attempt at a Solution So, I've gotten the first derivative...

Homework Statement I have to show a proof that if a is odd, b is even, and c is even but not divisible by 4. a,b,c are int coefficients ax2 + bx + c = 0 has no rational solutions Homework Equations all letters here are integers. So i have, a = 2d + 1 b = 2f c = 2g, but c...

Homework Statement A train slows down with constant deceleration a. A boy in the train drops an apple. What path does the boy observe the apple to take? Find an equation y=f(x) to describe the trajectory of the apple. Also, if the original height of the apple was yo, calculate how far...

1. While reading notes on group theory there is a step I could not reproduce although it seems to me it should be straightforward. Probably there is something I am missing on tensor indices notation. Since R is an orthogonal matrix you can... 2 ...go from \epsilon...

Homework Statement how do you go about solving the equation lim (t->0) 2t / (sin(t)) - t the answer in the text is significantly different than what i get.. i can get most of the other trig limits using the fundamental limit etc.. but this one I am stuck ? i may be way over...

Stuck on Stress/compression/tension----->pic included http://i44.photobucket.com/albums/f46/maximus11373/1-1.jpg All info is in the link above I am stuck on the problem for the longest time. What I do know is that bending will be at point B and compression at point A. I just don't...

Homework Statement Two buses are moving at constant speeds, in the same direction, the first at 42 km/h and the second at 54 km/h. They are 18 km apart. How long will it take the second bus to catch up to the first? (4 marks) Homework Equations average velocity = d/t The Attempt...

Homework Statement I need to find the inverse to element in 7 in ring Z_{13} Homework Equations 7^-1 in Z_{13} The Attempt at a Solution Needs to find X so that, 7x=1 in Z_{13} => 7x=1+k*13 And then my notes was messed up :(

Homework Statement I am trying to determine if an diophantine equation is solveable or not. And got stuck at one point. Homework Equations 61x+37y=2 The Attempt at a Solution I've found the gcd(61,37)=1 by: 61/37=1 %24 37/24=1 %13 24/13=1 %11 13/11=1 %2 11/2=5 %1 2/1=2 %0 So gcd(61,37)=1...

Homework Statement find f(a+h)-f(a)/h for the f (x)= 2x+3x2 Homework Equations f(a+h)-f(a)/h The Attempt at a Solution f(a+h)-f(a)/h =2(a+h)-3(a+h)2-2x+3x2 =2a+2h-3a2-3h2-2a+3a2 =2h-3h2/h that is where i am stuck help please

Precisely what does the following equation, in which R is the gas constant, allow one to calculate? ln xs = -dHf/R(T0-T/TT0) I have no idea what this could be. I know what each part of the equation is (gas constant, change in enthalpy of formation, Freezing point depression etc.) I...

Homework Statement Find a singular value decomposition of A. A^T= [7 0 5 1 0 5] Homework Equations A = U\SigmaV^T The Attempt at a Solution I started by doing A^T*A = [ 74 32 32 26] Then i went and found the two eigen values lambda1= 90 and lambda2= 10 and the...

Hey guys, this is the question i have been givin. i have been stuck on it for a while now, and i keep getting overly large numbers? such as over the 10000N range.. and according to the ansers its no where near that figure, i have about 2 pages of scrap notes i tried working out, in the...

Homework Statement the weight of items produced by a production line is normally distributed with a mean of 12 ounces and a standard deviation of 2 ounces. Suppose that quality control requires the weight of items to be within 8 and 16 ounces. You select 7 items at random (each item is...

I feel at bit down seeing how all my grades averaged out to be in the 80s, but no more than 85s. I tried a summer course this summer and I thought I could concentrate better, but I still ended up with an 80. When I look at some grad school applications, they all demand a minimum of 80 to even...

Homework Statement It's hard to explain, I can do everything exept get the answer to what I'v pointed out below. I just don't know what order to solve it into get the correct answer, I must have tried every method except the right one! Homework Equations The Attempt at a...

If A = 5ax + 3ay + 2az B = -ax + 4ay + 6az C = 8ax + 2ay Find the value of m and n such that mA + nB + C is parallel to y-axis. My problem is I did not know how to determine the m and n value because I did not know what method can use to solve for mA + nB + C parallel to y axis...

Homework Statement A slide projector needs to create a 81 cm high image of a 2.0 cm tall slide. The screen is 360 cm from the slide. Assume that it is a thin lens. What focal length does the lens need? How far should you place the lens from the slide? Homework Equations 1/f = 1/s +...

ok, here's the problem. I've got a pan stuck (horizontally) flat inside a pressure cooker and I just can't get it out. The outer circumference of the pan is exactly the same at the inner circumference of the pressure cooker and I have things under this pan which I was heating in the pressure...

Homework Statement So here are the two pages of the project: http://img.photobucket.com/albums/1003/aliceinunderwear/Calc2project1.jpg http://img.photobucket.com/albums/1003/aliceinunderwear/Calc2project2.jpg Homework Equations Calc stuff, integrals in general. d=rt The Attempt at a...

So I've got my exam of analysis tomorrow, but there's this piece of improper integrals I just don't get... (I'll paraphrase the definition we saw into english) So if f is not necessarily Rieman-integrable over ]a,b[ (a and b can be (negative) infinity), but for all c,d with a<c<d<b \int_c^d f...

Homework Statement A 1300kg car moving east collided with a 2600 kg SUV moving north at 28 m/s. The vehicles became stuck together . If the speed of the vehicles immediately after the collision was 30 m/s, what was their direction? A) 21 degrees E of N B) 52 degrees E of N C) 58 degrees E of...

Homework Statement \lim_{t \to \infty} \frac {5t+2}{t^{2}-6t+1} Homework Equations The Attempt at a Solution Like the title says i am quite stuck, I don't see the first move to make, so if someone could point me in the right direction instead of telling me the answer it would be...

Homework Statement Hey people, my professor game us an assignment of dozens of limits to resolve. Most of them I managed to resolve, but two. I don't don't if it's something I can't resolve because I need more practice but it seems that I am really stuck with them. So if you can give me some...

Help! Identifying a unknown aromatic ketone--we're stuck in a rut! Homework Statement My 12th grade O'chem lab has been given an unknown organic compound. We have tested it and know the following: BP-~214 degrees C Soluble in H2SO4 Neutral compound Aromatic ketone No Nitrogen present...