Recent content by tiffanysnsd

I believe I should clarify myself a bit more. As you can see from my diagram in my original post, the calculated angle clearly uses the x-axis as the reference. So one would expect that using the tan trig ratio to calculate the angle, dividing the y-component by the x-component, the correct...

Does my rationalization not make sense (or is inapplicable) or do you just think explanations along these lines are useless, provided I know how to approach the problems? It isn't really so much for this problem that I made this inquiry, but I don't want to be caught with my pants down again in...

Thank you, that is reassuring. Do you suppose I could rationalize it the following way: Instead of using the angle of 37* for my calculations, I would use 143* (considering the vector for q2 points northwest and would lie in the second quadrant on a cartesian plane, so 180-37=143). Therefore...

Oh, I apologize for that. The top point is q1.

Sure. Three charges are arranged as shown: http://img8.imageshack.us/img8/1841/82829031.jpg where, q1 = 2.5x10E-17 q2 = 3.0x10E-17 q3 = 3.5x10E-17 (all are positively charged) Calculate the magnitude and direction of the force acting on q1. Let up and right be positive...

So I have constructed this vector for a physics problem: http://img23.imageshack.us/img23/1753/vectorx.jpg Why is it when I take the tangent of the labelled angle, I get an angle of 77*, which is the complementary pair for the correct angle (which is 13*). I can rationalize this by...

That is sound advice. I am usually not mindful of what my angle should approximately be and accordingly entrust that task to my calculator. If the solution had eluded me for longer than it had, I would eventually make use of that to make sense of it - but thanks for the advice; I think it is...

This is a net force problem that I have solved, I would just like to clarify some aspects of my work. I will not post the details of the question, but it involves calculating the net force of two charges on another charge. I have defined up and right as positive. I did this solution using...

But my textbook writes: "Begin by tying the string to one of the plastic combs and suspending this comb from the edge of a table so that it hangs freely. Rub the suspended comb in wool to give it a negative charge. Plastic rubbed in wool acquires a negative charge, so plastic is more...

Well if the first of the two combs, the testing device, is permanently charged (by wool), then don't the objects you bring near it need to be charged? Like I said, the book instructs that the comb charged by wool and the objects, one by one, will be brought within proximity. So both would need...

If this is of any use, my textbook specifically instructs that the comb charged by wool is to be brought into proximity with the object/material; the two combs will not be brought into near contact with each other.

I considered that possibility, that touching the second comb would serve to ground it. So let me get this straight, if the second comb is suspended and rubbed against an object or material, it will serve to charge the object? Would I not be grounding the object by holding it?

Ahh, that was my guess. What threw me off was the mention of two strings corresponding to each of the combs. Why two combs AND two strings? It doesn't seem necessary to hang the second comb. The other thing was that my textbook instructed that I also use materials such as rubber and glass...

Yes, that is already clear. I am seeking the purpose of the second comb, if there is any. Also, I am seeking to know whether I have to charge the objects myself (perhaps using the second comb), or whether I can expect to find them partially charged in their natural state.

So I have to do a lab, where I rank common household materials based on electronegativity. I am told to acquire two plastic combs and two pieces of string with which to hang them freely off a table. Besides that, I am to acquire common household materials such as rubber, wool, cotton, glass...