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    Magnetisim Problem! Just need an Equation.

    Here's the problem: A proton follows a spiral path through a gas in a magnetic field of 0.010 T, perpendicular ot hte plane of the spiral. In two successive loops at points P and Q, the radii are 1.0 mm and 8.5 mm respectively. Calcualte hte hcnage in the kinetic energy of hte proton as it...
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    Point Charge Check?

    thanks docAl it should be invcos(43/55) to get 38.57 degrees.. Hm. but still not the right answer.
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    Point Charge Check?

    Point Charge Check!? Hi, I' did this problem but for some reason I'm not getting the right answer. If you could check to see where I made my mistake I'd really appreciate it. Thanks! The problem: A poitn charge (m=1 g) at the end of an insulating string of length 55 cm is observed to be...
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    Any Hints?

    I did that, but I don't know how to put the information into formulas
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    Any Hints?

    Nobody!?! Please help! I have a quiz this friday! I really need to know how to do these problems!!!
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    Any Hints?

    Any Hints!?!? I'm stuck on these 2 problems.. Any hints would be helpful! 1. What is the minimum work needed to push a 950-kg car 810m up along a 9 degree incline? a) ignore friction, b) assume the effective coefficient of a friction retarding the car is .25. This is what I did, but I...
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    Conservation of Energy Problem.

    At the highest point, vertical velocity is 0, and no, the horizontal velocity isn't affected... so then my final velocity would be zero, and y1 will be zero. This leaves me with 28.8-20 = (.40)(9.8)y2 y2 = 2.21 meters. Can anyone verify my answer?
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    Conservation of Energy Problem.

    Here's the problem: A .40 kg ball is thrown with a speed of 12m/s at an angle of 33 degrees. a) what is its speed at its highest point, and b) how high does it go? (Use conservat ionfo energy and ignore air resistance) I think I'm supposed to use the formula .5mvi^2 + mgy1 = .5mvf^2+mgy2 ...
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    Magnitude and direction for the total gravitational force

    So then,could I do this for the first force? Fm1m2 = (Gm1m2)/r^2 = G(9.5)(9.5)/(.601)^2 = 250.694G ?
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    Magnitude and direction for the total gravitational force

    Those unit vectors are unknowns, right?
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    Magnitude and direction for the total gravitational force

    I still don't quite understand. This is what I've done so far. I've drawn four spheres, one at each corner of the square. I've draw vectors from three spheres all pointing to the same one sphere. I've labeled the vectors A (the one pointing in the x direction) vector B, (pointing downwards...
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    Magnitude and direction for the total gravitational force

    I've done your step 1, I've drawn the vectors, three vectors one going from each of the three spheres to the same one sphere. Am I setting this up correctly? I know how to find the x and y components, but what would the resultant vector look like? I dont' understand how there can be one if all...
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    Magnitude and direction for the total gravitational force

    Please help me with the following problems!! Four 9.5 kg spheres are located at the corners of a squareof side .60m. calculate the magnitude and direction fo the total gravitational force exerted on one sphere by the other three. *I think I'm supposed to use the forumula : F= G(m1)(m2)/r^2...
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    What am I doing wrong?

    Yes, sorry about that... I actually got 1.5 m/s^2.
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    What am I doing wrong?

    OHh I see. Though I did it incorrectly I got the same answer. Everything makes sense now. Thanks for the help!
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    What am I doing wrong?

    T= 320 x .15 = 48 + 320 = 368 N F=ma 368= 320a a= 1.15 m/s^2 . This is correct! However, I have another quick question. For part a and for the first part of part b, I solved for the tension when they asked for her force. How is her force equal to the tension of the rope? Shouldn't it be...
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    What am I doing wrong?

    will I use Newton's formula to figure out this change in tension?
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    What am I doing wrong?

    Got part a. Thanks - For part b. I take .15 x 320 = 48 320+48=368. F= ma 368/65 = a a= 5.66? What am I doing wrong here? It should be 1.5 ...
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    What am I doing wrong?

    Oh I see.. So because we are using a pulley system, there is tension on each side of the pulley . So would I solve 2T-mg = ma 2T-637 = 0 =318.5 or about 320. So is it okay to assume that 1 pulley will always divide the force needed in half?
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    What am I doing wrong?

    Because the problem was in a chapter dealing with forces, I'm assuming that's what they're asking for. Also by asking how hard must she pull downwards, doeson't that ask for the force she has must exert onto the rope to pull herself down? :bugeye:
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    What am I doing wrong?

    I found this question to be answered twice on this site, both by hallsofivy. However, I still don't quite get it. Please help. A window washer pulls herself upward using the bucket pulley appartus. a. how hard must she pull downward to raise herself slowly at constant speed? b. if she...
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    Physics tips . ?

    Thank you all for your suggestions! I'm open to more, please continue posting!
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    Physics tips . ?

    That's one of my habits.. But it's the only way I know how to go about the problem! Please elaborate what you mean by 'starting with a basic principle.'
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    Physics tips . ?

    This is my first year of physics . On the first day my professor had already told us that we would be learning physics differently than any other class we would be taking. I had been able to zoom through all of my other classes like econ, pysch, english, math, chem, bio etc. For physics however...
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    Solved it; Don't understand it.

    I did the problem, got the correct answer but dont' know why I was supposed to do it this way! Please help me understand the reasoning behind all this: A swimming is capable of swimming .45m/s in still water. She is swimming across a 75 m wide river whose current is .40 m/s. A) at what...
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    Trajectory of diver with vertical and horizontal velocities

    Please help me with this problem! :yuck: :confused: :surprised I can't seem to get it set up quite right. A high diver leaves the end of a 5 m high diving board and strikes the water 1.3s later 3 m beyond the end of the board. Considering the diver as a particle,d etermine a) her initial...
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