Find the induced electromotive force (epsilon)

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Handwritten sketch of a right-angled triangular loop with a 37 degree angle at the base, a red rod AC moving right with velocity v, and crosses marking an into-page magnetic field. Beside it are the lines epsilon = -delta phi / delta t, phi = B S cos alpha, and S2 - S1 = l v delta t.
Handwritten sketch of a right-angled triangular loop with a 37 degree angle at the base, a red rod AC moving right with velocity v, and crosses marking an into-page magnetic field. Beside it are the lines epsilon = -delta phi / delta t, phi = B S cos alpha, and S2 - S1 = l v delta t.
it is something like this but instead of the rectalve contour iswith the angle 37 degree!https://www.physicsforums.com/attachments/114624 1. Homework Statement

the speed of the slide is 0.16 m/s
the length of the slide is 0.14 m
the angle of the contour is 37 degree

Homework Equations


inducted electromotoric force=-delta phi/delta time
phi=induction(B)*surface*cos alpha (alpha=0 degree)[/B]

The Attempt at a Solution

https://drive.google.com/file/d/0BxmarOZtFg5FdEJDWkNaRnVZX00/view?usp=sharing [/B]
 
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1. Your problem description is too vague. "something like this" is not good enough. There's no way to know what your 37° angle pertains to.

2. Your image of your attempt at solution is all but illegible (too dark, out of focus). If necessary, type in your solution and only provide images for diagrams.
 
gneill said:
1. Your problem description is too vague. "something like this" is not good enough. There's no way to know what your 37° angle pertains to.

2. Your image of your attempt at solution is all but illegible (too dark, out of focus). If necessary, type in your solution and only provide images for diagrams.
gneill said:
1. Your problem description is too vague. "something like this" is not good enough. There's no way to know what your 37° angle pertains to.

2. Your image of your attempt at solution is all but illegible (too dark, out of focus). If necessary, type in your solution and only provide images for diagrams.
 
Attachments
  • Handwritten physics sketch of a conducting rod AC moving at v = 0.15 m/s across a rail inclined at 37 degrees, with crosses showing a magnetic field into the page; handwritten working for induced EMF uses epsilon = -B(S2 - S1)/delta t.
    Untitled.png
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It looks like the slider will lose contact with the two arms of the contour immediately after it passes the points AC. Is that intended?

Since the rate of change of the area of the closed loop will change with time, the EMF will change with time, too. Is there a particular instant in time or position of the slider for which you need to find the EMF?

You need to take your time to thoroughly prepare your problem description so that others can quickly and easily understand the details.
 
The slider will continue to to slide (mayby it can stretch?? I don't know ,but I am pretty sure that's not the case here) we have explained before in class what happens in a rectangle contour (the surface becomes l*dt*v and dt is being simplyfied with dt down and epsilon becomes -Blv) this is the exact thibg but ibstead of the S=l*dt*v it is more complicated because we should find the surface of the triangle above (right triangle with 37degree abgle ) this surface + the surface of yhe rectanglr should give a surface which has an dt inside (this dt sbould the be simplified with the dt down and should give the answer but this is fifficult to get a firmula with only one dt (this is mostly a trigonometric exercisr) si pls help because I am really stuck (my teacher gave it only to me this exc. Causev I am the best in my class and i can't let her down)
 
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It looks like you want to find the EMF at the specific instant that the line AC is 14 cm in length. Suppose that at that instant that the two legs of the right angle triangle are x and y, with y being coincident with the line AC. How might you solve for x given the angle and value for y?

Diagram of a right triangle with angle θ at the lower left, base x along the bottom and vertical side y, inside a uniform field of inward-pointing crosses, with a blue vertical rod moving right at speed v.


Then, what's the area of the triangle in terms of x?