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    This magnet question confounds me

    Homework Statement Today, my teacher gave us some practice AP multiple choice and my friend and I were debating between answer choices H and J (changed from A and B to remove any confusion) the question as i remember it: blah blah... B-field into the page, constant velocity v, radius R and...
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    Need help with gauss law and charged ring AP Physics FRQ

    Homework Statement 1. 2. Homework Equations ∫E.dA = Qenc/\epsilon_{o} \lambda=Q/L \rho=Q/V V= q/4πε_{o}r The Attempt at a Solution these types of problems i suck at, i dont know how to do these at all independently, and is there any difference in question 2 if there is an insulator or...
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    Which option should I do?

    It's your choice I pick particle physics
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    Schools What should i expect in physics in college?

    Yea I'm in physics C now Say my major could be neuroscience or biochem
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    How can I be really fast at maths?

    im no expert at this stuff but when i was practicing for the SAT i would take off a small chunk of time from the allotted time. for example, if a section is 25 mins 24 questions, i would give myself 20 mins for 24 questions. overtime i was able to get faster. on test day, i finished the...
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    How do/did you study Physics?

    this is how i do it 1. try to solve the problem as long as possible without going to the solution 2. go ask somebody for helping hints and try again 3. look at solution understand what is going on 4. try the problem again
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    Schools What should i expect in physics in college?

    First off, sorry for wrong location of post. I am wondering what kind of stuff you guys do in college physics. Is it similar to AP Physics? What should I expect in the Biochemistry Major, I was looking at the suggested courses on my future college's website and I think it was something like Gen...
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    Current in a rectangle on a hinge

    τ=μ × B μ=NiA τ=NiABsin30 τ=(15)(.9)(.1*.05)(.5)sin30 τ=.16875 Nm
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    Current in a rectangle on a hinge

    Homework Statement Figure 29-36 shows a rectangular, 15-turn coil of wire, 10 cm by 5.0 cm. It carries a current of 0.90 A and is hinged along one long side. It is mounted in the xy plane, at an angle of 30° to the direction of a uniform magnetic field of 0.50 T. Find the magnitude and...
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    Circuit help - resistors and batteries in a network

    1) -1.5-3(i1)-2.5(i2)=0 2) -2.5(i2)-3(i3)=0 3) -1.5-3(i1)-3(i3)=0 1) 1.5=-3(i1)-2.5(i2) 2)-2.5(i2)=3(i3) 3)1.5=-3(i1)-3(i3)
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    Circuit help - resistors and batteries in a network

    ok i just redid my loops im not sure what is going wrong 1) 2-1.5(i1)-2.5(i2)-3.5-1.5(i1)=0 2) 3.5-2.5(i2)-1.5(i3)-3.5-1.5(i3)=0 3) 2-1.5(i1)-1.5(i3)-3.5-1.5(i3)-1.5(i1)=0 1) -.6-1.2(i1)=i2 2)-.833(i2)=i3 3)-.5-i3=i1
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    Circuit help - resistors and batteries in a network

    ok so i set up 3 loops and after simplifying i get: Loop 1(the square on the left):-.6+1.2(i1)= i2 Loop 2(right square): 2.5(i2)=1.5(i3) loop 3(the whole rectangle): 1.5=-3(i1+i2) and that i1 = i2+i3
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    Circuit help - resistors and batteries in a network

    circuit help -- resistors and batteries in a network Homework Statement (a) Calculate the current through each ideal battery in Fig. 28-41. (As a sign convention, assume the currents are "up" through each battery.) A (I1) A (I2) A (I3) Assume that R1 = 1.5 , R2 = 2.5 ...
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    Electric potential of tiny spheres question

    Homework Statement Two tiny metal spheres A and B of mass mA = 3.40 g and mB = 3.90 g have equal positive charges q = 4.50 µC. The spheres are connected by a massless nonconducting string of length d = 1.00 m, a distance that is much greater than the radii of the spheres. (a) What is the...
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    How do i find acceleration givin initial velocity, final velocity, and displacement?

    since (X-X0) is 25-0 you can move variables around and solve for a
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    Why does the E-field inside a cylinder =0?

    Homework Statement Figure 24-32 shows a section of a long, thin-walled metal tube of radius R, carrying a charge per unit length  on its surface. Derive expressions for E in terms of distance R from the tube axis, considering both (a) r > R and (b) r < R. Plot your results for the r = 0 to...