Recent content by fannemel

When i do the calculations myself i got F_e = 8.99x10^{45} but your first line is correct, probably just forgot to square the the distance when calculating the answer... For the other question, we know that electrical charge is quantized and the smallest possible charge being the...

now, i have always thought that in mathematics you had to be consistent, is ellen girlfriend or girlfiend? :-p

For the first question you use the formula for electric force, hint: it's the one that resembles Newtons law of gravity. For the second one, consider what charge N number of electrons sum up to.

Conservation of energy means in this case (actually most of the time friction and such forces aren't applied) that: \frac{1}{2}mv^2 + mgh = k where k is a constant if you use that you will find that \frac{1}{2}mv^2_t + mgh = \frac{1}{2}mv^2_b where h = 2r (the difference in...

The heaviside function is most easily explained as a on-switch. h(u) = \left\{ \begin{array}{rcl} \ 0 & \mbox{for} & t < u\right \\ 1 & \mbox{for} & t \geqq u \end{array}\right Thus if you multiply a function with the Heaviside function, the output are zero until the t = u, from that...

3 and 5 are not correct. Consider using conservation of energy.

F = kx E_p = \int F dx = \frac{1}{2} k x^2 Energy in spring The only force working on the object is the force from the spring

what about \frac{Im_{z2}}{x^2 + y^2} = I am [\frac{1}{z1}] Would that be any better? For me that would equal: {\frac{-y}{x^2 + y^2} = I am [\frac{1}{z1}] since Im_{z2} = -y

Problem 4: An electron has charge, and it's charge is the smallest amount of charge possible. Thus all greater charges equals a whole number of those. Formula would be: Nq = 12mC where N = number of electron and q = e the electron charge = 1.60 * 10^-19 then you can find how many...

oops, read another post and found that it would be wise to post my work. And i reckoned that no-one would have had the time to reply so i just edited my post. But do my new post clarify anything?

z1 = x + iy z2 = x - iy (Complex conjugate) Find: Im (1/z1) This is what I have tried to do: (1) z1*z2 = x^2 + y^2 (2) z2 / (x^2 + y^2) = 1 / z1 The answer is: -y / (x^2 + y^2) = I am (1 / z1) So my question is: Can I change z2 to I am (z2) and z1 to I am (z1) in...