Recent content by Kalibasa

  1. K

    Fun question- what tricks can you do with a circuit through your body?

    My boyfriend is into magic, and he has a device that sends a small current through his body. His shoe has an electrode that is activated by a magnet in his other shoe; a wire runs up to a battery. As long as he is standing and grounded, it allows him to channel a small amount of electricity...
  2. K

    Electric potential and charge on capacitors-

    So I finally gave up and got the answer from someone else, and I'll post it here since you'll probably be curious now! The answer we got for Q2 was clearly wrong (these values all worked in my online homework, so they must be right). But I have no idea why our method didn't work- I don't see...
  3. K

    Electric potential and charge on capacitors-

    It's asking for the charges and the deltaV's on each one, though- I'm doing an online homework and there are six boxes to fill in. It's telling me that that value for Q2 is wrong. So I don't know. Maybe I'll try putting in a deltaV I've calculated off of that and see, but I don't know what...
  4. K

    Electric potential and charge on capacitors-

    I did exactly what you listed up there. Starting with the last equation you lsited, I multiplied both sides of the equation by C2 and by C3 in order to get a like denominator. This gave me [C3*C2*(0.0012-2Q2)]/C1=C3Q2 + Q2C2. Then I plugged in numbers for all the capacitances: [30 * 16 *...
  5. K

    Electric potential and charge on capacitors-

    I've mixed up C for capacitance and C for coulomb many times so far ;) Thanks for the help, but I am still getting the wrong answers! And I did assume that you meant Q1+Q2+Q3= .0012. Since your post I tried two things. I tried reworking the second equation as you said to Q1/C1= Q2/C2 + Q3/C3...
  6. K

    Electric potential and charge on capacitors-

    For the last equation, did you mean Q1 + Q2 +Q3= 0.0012? Or do you really mean the sum of the capacitances?
  7. K

    Electric potential and charge on capacitors-

    Homework Statement Consider the circuit in the figure below, in which C2 = 16 µF and V = 80 V. Initially, the switch in is in position A and capacitors C2 and C3 are uncharged. Then the switch is flipped to position B. Afterward, what are the charge on and the potential difference across...
  8. K

    HELP Finding the focal length of a lens, I'm totally stuck

    Oh! That's exactly what I did except that I did -40.5 + 1 = -39.5 instead of 40.5+ 1= 41.5. Maybe I got too caught up in the signs from the equation... Ok thank you so much! Haha that took a lot of posts
  9. K

    HELP Finding the focal length of a lens, I'm totally stuck

    Simultaneous equations? What do you mean? Haha I haven't taken algebra in ten years and maybe it's showing... :uhh:
  10. K

    HELP Finding the focal length of a lens, I'm totally stuck

    I already know that s' + s= 360, but that hasn't helped. I know it's a vital piece of information, but I don't know how to use it- everything I've tried hasn't worked
  11. K

    HELP Finding the focal length of a lens, I'm totally stuck

    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 +...
  12. K

    What is the Angle ϕ of the Reflected Laser Beam in Plane Mirror Reflection?

    How I tried to do it algebraically was a long complicated mess, which is why I didn't post it. I finally figured it out, though- my starting angle was 42.5 degrees, that's what I'd missed, and then I was able to calculate each angle as I went around
  13. K

    What is the Angle ϕ of the Reflected Laser Beam in Plane Mirror Reflection?

    Homework Statement A laser beam is incident on the left mirror in the figure below, in which α = 85°. Its initial direction is parallel to a line that bisects the mirrors. What is the angle ϕ of the reflected laser beam? http://www.webassign.net/knight/p23-40.gif" Homework Equations...
  14. K

    Wave optics and diffraction gratings

    I tried that, though. The first fringe was at 17.45 degrees, so I figured you could go out to only 90 degrees in each direction; this means you could fit five fringes in either direction, plus the one in the middle, so 11 total. Doesn't that make sense? But the book says there are supposed to...
  15. K

    Wave optics and diffraction gratings

    Homework Statement I'm really struggling with this one. "A diffraction grating with 600 lines/mm is illuminated with light of wavelength 500 nm. A very wide viewing screen is 2.0 m behind the grating." a) What is the distance between the two m=1 fringes? b) How many bright fringes can...
Back
Top