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    Electric Field and Electric Potential Question

    oh, I totally skipped that: it would be Magnitude 5.1x10^6 N/C to the south east (45 degrees below the positive x-axis? Thank you for your help!
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    Relativity Question

    now this makes total sense. Since I have no length in either frame I cannot use the Length contraction equation. The 10 years I plugged into the length contraction equation is not a length but a time... Thank you for helping me with this Vela. I greatly appreciate it...
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    Relativity Question

    If I use d=vt I get: d=0.80c(10years) = 8 Lightyears for the people on earth and d=0.80(6years) = 4.8 Lightyears for the astronauts I was under the impression that d=vt was not valid for speeds close to the speed of light? (I'm a little confused was finding the distance via the...
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    Electric Field and Electric Potential Question

    Homework Statement You have a Square with 10cm lengths on each side. Charges of +4 microC (top right corner), -6 microC (top left corner), and +4 microC (bottom left corner) are located at three corners of the square. A) Calculate the electric field in the empty corner of the square. B)...
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    Relativity Question

    The only formula I thought fit after doing multiple relativity questions was Length contraction for a question like this. Is there another way to solve it? I tried time dilation first thinking time/years seems reasonable, but my answers were wacky. But it may have been a mathematical error...
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    Light after a Polarizer Question

    Homework Statement Initially unpolarized light with an intensity of 240W/m2 is incident on a series of two polarizers. What should be the angle between to the axes of the two polarizers such that the transmitted intensity after the second polarizer is 37.5% of the incident one? Homework...
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    Relativity Question

    Distance on earth inertial frame = 0.80c(10years) = 8yc (does yc = light years?) Distance on spaceships inertial frame 0.80c(6years) = 4.8yc Thanks... does all the other stuff look correct? Thanks for your help
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    Relativity Question

    Homework Statement A) at what velocity will be the KE of a spaceship 2/3 of its rest energy? B) If the Spaceship travels at this velocity relative to the earth and its trip takes 10 years as measured in the earthbound system, how much time has elapsed on the spaceship clock? C) What is the...
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    Double Slit Interference Question

    Thanks! Definitely a typo, sorry about that.
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    Double Slit Interference Question

    Homework Statement Light of wavelength 680 nm falls on two slits and produces an interference pattern in which thefourth-order fringe is 38 mm from the central fringe on a screen 2.0 m away. What is the separationof the two slits? Homework Equations Sintheta=2m(\lambda2d)...
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    Lens Combination Question.

    The object distance is defined as the distance between the object and the lens. for the first lens i got an image distance of 125cm. This goes beyond the second lens so to consider the first image as the second object wouldn't i have to subtract the distance in between the two lens and the...
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    Converging Lens Problem

    Any more advice on this? Thanks!
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    Lens Combination Question.

    Homework Statement Two 28.0-cm-focal-length converging lenses are placed 16.5 cm apart. An object is placed 36.0 cm in front of one lens. Where will the final image be formed by the second lens? Homework Equations 1/do + 1/di = 1/f The Attempt at a Solution for the first...
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    Converging Lens Problem

    A real image is inverted and m should be negative m= -di/do -2= -di/do do= -di/-2 If this is correct then 1/do+ 1/di = 1/f -2/-di + 1/di = 1/f hmmm I'm stuck after this
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    Converging Lens Problem

    so for this part: Now i have to use the lens equation: 1/do+ 1/di = 1/f -(2/di) + 1/di = 1/f -1m/di = 1/f di= -1m/(1/f) di = (-1 x 2)/(1/50mm) di = -100 it should be: di= -1m/(1/f) di = (-1 x -2)/(1/50mm) di = +100mm so do = -di/m = -100/-2 = +50mm in the back of the book it says the answer...
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    Optics: 2 lens problem

    Now I get it, Thank you very much for all your help ehild
  17. I

    Optics: 2 lens problem

    I have written in my notes that it should be 27cm from the first lens. Question, why wouldn't it be considered 27cm from the object? Is it when us the lens equation we are always dealing with the image length relative to the lens and not the object? Thanks for your help!
  18. I

    Converging Lens Problem

    Homework Statement (a)How far from a 50.0-mm-focal-length lens must an object beplaced if its image is to be magnified 2.00 x and be real? (b)What if the image is to be virtual and magnified 2.00x? Homework Equations m = -di/do 1/do+ 1/di = 1/f The Attempt at a Solution m...
  19. I

    Optics: 2 lens problem

    it is 12 cm to the right of the second lens. So here the object is -12cm to the lens, so instead of using positive 12 for the second lens equation i should have used -12. 1/di2 = 1/4cm - 1/-12 = 4/12cm = 3cm di1+di2 = 24cm + 3cm = 27cm ?
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    Optics: 2 lens problem

    the image is outside, all the way to the right.
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    Optics: 2 lens problem

    The image after the first lens is 12cm to the left of the second lens. Im confused as what is in front and behind when it comes to the second lens. Do i take the left as front and right as back (like i did for the first lens), or is this reversed when talking about the second lens? Thank...
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    Optics: 2 lens problem

    Homework Statement We have a convex lens with a focal length of 8cm, which is 12cm from the second converging lens that has a focal length of 4cm. An object is 12cm from the first lens. Where is the final image? Homework Equations 1/do + 1/di = 1/f The Attempt at a Solution So...
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    Sinusoidal in time

    Hi, I having trouble grasping what: "oscillatory motions are sinusoidal in time" means... does this just mean that when solving a problem for simple harmonic motion that the equation is going to involve both and sin/cos and time? Sorry this might be more of a mathematical question.
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    Find the Net Force and Acceleration Question

    Awesome! I think this thread has helped me understand more than just the problem but on how to calculate the direction of a vector within a plane. Thank you so much for all your help, its greatly appreciated!
  25. I

    Find the Net Force and Acceleration Question

    Ok, so I first drew a line with magnitude 10.2 going to the right (east), then I drew a line down (south) from the tip of east line. From there I drew a line from the tail of the east line to the head of the south line (tail to tip method). I have 10.2 as my x and 16.0 as my y. my hypotenuse...
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    Newtons Law and Friction Question (along with a contact force question)

    hmmm. what I did was first find the contact force which I set up like this: Contact force = Force - Ffriction - ma Contact force = 620N - 110.25N - (75x9.8) Contact force = 367.25 but I rounded to +370N the + is the contact force exerted on the 110kg box by the 75kg box. So for the...
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    Newtons Law and Friction Question (along with a contact force question)

    The picture just has a table with the two blocks on top of it with an arrow pointing to the blocks, indicating the 620N force. I put the minus sign because Newtons Third Law "for every action there is an equal but opposite reaction" So if the 75kg block has a contact force of 320 on the...
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    Find the Net Force and Acceleration Question

    So if I'm following you correctly: The components of the first situation is: x= -10.2 y= -16.0 Theata = 51o (when doing this I'm not entirely sure from what axis it is, I did tan-1(-16/-10.2) The components of the second situation: x = 8.8 y = 10.9 theta = 51o (again I dont know...
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    Newtons Law and Friction Question (along with a contact force question)

    I follow. I think I got confused when doing the problem. Is this correct? So for Question b: I got the Contact force as 370N of the 75kg block on the 110kg block and -370N of the 110kg block on the 75kg block. Now for part c: If I go to the other side of the table and apply a 620N...
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