Search results

  1. D

    Finding mixture concentration using Beer's Law

    I'm still slightly confused on how that would look? Are you saying we do: A1/A2 = (b1C1e1)/(b2C2e2)?
  2. D

    Introductory to chem course Stoichometry question wrong answer, can anyone fix it

    What I do is convert everything to moles (mmoles) in order to figure it out. 19.62 mL * 0.341 M NaOH = 6.69 mmoles OH- To completely neutralize that, you need an equivalent in H+, so you need 6.69 mmoles H+. However, H2C2O4 produces 2 H+ per dissociation, so you would need half that amount, or...
  3. D

    Finding mixture concentration using Beer's Law

    Homework Statement A 0.0450 M solution of para-aminobenzoic acid had an absorbance of 0.844 at 267 nm in a 1.00 cm cuvet, and an absorbance of 0.034 at 240 nm. A 0.0366 M solution of nicotinic acid had absorbances of 0.010 and 0.755 at 267 and 240 nm, respectively. A MIXTURE of PABA and...
  4. D

    Curly Electric Fields

    Not much because I don't know what to do with it. What would the flux be? Would it be emf = -dΦ/dt Φ = BxA emf = (-d/dt)BxA? Does B = B0 + bt^3?
  5. D

    Curly Electric Fields

    Homework Statement The magnetic field is uniform and out of the page inside a circle of radius R, and is essentially zero outside the circular region (see the figure). The magnitude of the magnetic field is changing with time; as a function of time the magnitude of the magnetic field is...
  6. D

    A neutral metal rod in a uniform magnetic field

    Wait a minute, I got it; the stupid thing wants to the ABSOLUTE VALUE.
  7. D

    A neutral metal rod in a uniform magnetic field

    Homework Statement A neutral metal rod of length 0.35 m slides horizontally at a constant speed of 9 m/s on frictionless insulating rails through a region of uniform magnetic field of magnitude 0.6 tesla, directed into the page as shown in the diagram. Before answering the following...
  8. D

    Circuits and Loop Rule

    Homework Statement Write the loop rule for each of the following circuits: Homework Equations Depending on the loop: -emf + IR1 + IR2 + .... + IRn = 0 V = IR If in series: R1 + R2 + ... Rn = R If in parallel: 1/R1 + 1/R2 + ... 1/Rn = 1/R The Attempt at a Solution I really...
  9. D

    Electric Field of Single-Battery Circuit with Thin/Thick Wires

    I solved it all on my own. I'll post the solution here so people will know how to do it if they come across it. i = naME i = electron current n = electron density a = area M = electron mobility E = electric field For the thin and thick wire, the electron current for both of them is...
  10. D

    Electric Field of Single-Battery Circuit with Thin/Thick Wires

    Homework Statement The circuit shown above consists of a single battery, whose emf is 1.4 V, and three wires made of the same material, but having different cross-sectional areas. Each thick wire has cross-sectional area 1.4e-6 m2, and is 21 cm long. The thin wire has cross-sectional area...
  11. D

    Charged capacitor, electric field

    http://i212.photobucket.com/albums/cc150/deadfishfactory/Untitled-1.jpg I don't know if that's any help. I did that, and it's still wrong.
  12. D

    Uniformly-charged Thin Rod

    http://www.csulb.edu/~htahsiri/studyguide/Mathematica/physics/chargerod/chargerod.html What is it supposed to be?
  13. D

    Uniformly-charged Thin Rod

    Homework Statement If the total charge on a rod of length 0.4 m is 2.6 nC, what is the magnitude of the electric field at a location 1 cm from the midpoint of the rod? Homework Equations [(2QK)/(Y)](1/sqrt(L^2 + 4[(Y)^2]), K = 8.99E9 I don't know if the above equation is actually correct...
  14. D

    Charged capacitor, electric field

    Thanks for that. It says that sparks occur when the electric field strength is 3x10^6 N/C. So if you have that, then: E = E1 + E2 E = [Q/(A/2e)] + [Q/(A/2e)] (R>>Z) 3x10^6 = 2[Q/(A/2e)] 3x10^6 = 2[Q/(pi(2.4)^2/2(8.58E-12)] Q = 3E20 N/C. What am I doing wrong here?
  15. D

    Charged capacitor, electric field

    Homework Statement A capacitor consists of two large metal disks of radius 2.4 meters placed parallel to each other, a distance of 0.7 millimeters apart. The capacitor is charged up to have an increasing amount of charge +Q on one disk and -Q on the other. At about what value of Q does a spark...
  16. D

    Electric Fields and source charge

    Homework Statement The source charge (the magenta circle at the origin) is a positive charge. A particle whose charge is -6e-09 C is placed at location D. 1. The electric field at location D has the value < -8000, 8000, 0 > N/C. What is the unit vector in the direction of E at this...
  17. D

    Electric Dipole Moment and electric field

    Oh, whoops. You're right. With the Y component for the x-axis, it would be E(y) = kqs/y^3 = (8.99E9 * 6E-9 * 0.001) / (0.06^3) = 250. 250 + 500 = 750; <0,750,0> Thanks.
  18. D

    Electric Dipole Moment and electric field

    Homework Statement Two dipoles are oriented as shown in the diagram below. Each dipole consists of two charges +q and -q, held apart by a rod of length s, and the center of each dipole is a distance d from location A. If q = 6 nC, s = 1 mm, and d = 6 cm, what is the electric field at location...
  19. D

    Rotation with pulleys

    Ohhhh. Pfft. When you said "heavier block falls 75.0 cm in 5.00 sec," it immediately smacked into me. Haha. I'm such an idiot for not noticing. Anyways, I got the answer. Thank you very much!
  20. D

    Rotation with pulleys

    Still having trouble finding the acceleration of the blocks. I found the angular acceleration of the pulleys by using the constant acceleration equation like you said. I got 1.22 rad/s^2, which is close enough. I can't figure out how to find the acceleration of the blocks since I used...
  21. D

    Rotation with pulleys

    Homework Statement A block has a mass of 500 g, another block has a mass of 460 g. Both are attached to a pulley with a frictionless wire that does not slip. The pulley, which is mounted in horizontal frictionless bearings, has a radius of 5.00 cm. When released from rest, the heavier block...
  22. D

    Completely Inelastic Collisions

    I did a problem similar to this one from a different text book with the values (everything is worded the same, except these values are in place): m1: 2.00 kg m2: 5.00 kg v1: 10.0 m/s v2: 3.00 m/s K=1120 N/m I approached this problem differenty when I drew the before and after reference...
  23. D

    Completely Inelastic Collisions

    Homework Statement A block of mass m1=1.88 kg slides along a frictionless table with a speed of 10.3 m/s. Directly in front of it, and moving in the same direction, is a block m2=4.92 kg moving at 3.27 m/s. A massless spring with a force constant k=1120N/m is attached to the backside of m2...
  24. D

    Box falling on a spring

    Homework Statement A 2.14 kg block is dropped from a height of 43.6 cm onto a spring of force constant 18.6 N/cm. Find the maximum distance the spring will be compressed. I know that the mass is 2.14 kg, the force constant of the spring is K=1860 N/m. I assume the final velocity, the...
  25. D

    Friction Forces and max braking force

    1. The coefficient of static friction between the tires of a car and a dry road is .62. The mass of the car is 1500 kg. What is the maximum braking force is obtainable: a. horizontal to the road. b. on an 8.6 degree downgrade? 2. F=mA f(s)=M(s)N N=mg F=f(s)-mgsin(x) 3. a...
Top