Recent content by stobbz

Ahh ok, thanks for the reply. I'd much rather you corrected me when I'm wrong :-) I think I was supposed to derive it, but I have no idea where to start. This is causing me untold misery! Thanks again.

Homework Statement A current carrying loop of wire is being monitored using a Hall-effect magnetic field probe placed at its centre. The loop is in air and has a radius of 0.5 m. It is required to monitor the magnetic flux in order to trip the circuit breaker if the current exceeds 100 A...

Ahh ok, now I see where I was going wrong! Thanks for walking me through that gneill, massively appreciate it.

r13 = (2, -2), unit vector r = root 2 / 2 in the x direction - root 2 / 2 in the y direction, F13 = Q1Q3 * unit vector / 4 PI Epsilon nought r^2 (with r = 2)

I used 4 (two squared) for the position vector and root 2/2 for the unit vector. This is for the x component for the force on q3 exerted by q1.

Ahh sorry, the given answer is 9.537 nN.

Nothing, I've changed it to avoid any more confusion :smile:

Homework Statement A charge +2nC is located at (0, 2 m). Another +2 nC charge is located at (0, -2 m). A third charge, +3 nC, is located at (2 m, 0). Calculate the total force (in vector form) acting on charge +3nC from both +2nC charges. Homework Equations Coulomb's law in vector form The...

Good to know I'm not too far off the mark, thanks a lot for the clarification Zryn.

The current enters the dotted terminal of L1. My understanding is, that means a positive voltage will be induced at the dotted terminal of L2. Going round the circuit in the direction of the current, wouldn't this produce a voltage rise across L2 (from undotted to dotted terminal)? In other...

Homework Statement Determine the polarity of the induced voltages in L1 and L2. [PLAIN]http://img406.imageshack.us/img406/730/31761140.jpg According to the dot convention rule, when current enters the dotted terminal of a coil,the polarity of the voltage it induces in the other coil is...

[PLAIN]http://img30.imageshack.us/img30/3306/counterty.jpg Is this an asynchronous down counter, or is it nonsense? (Assuming all J and K inputs are connected high) Trivial question, I know :-)

Homework Statement Two point charges, q1 = -2nC & q2 = +5nC are 4 cm apart. What is the force on q1? What is the force on q2? (Magnitude and Direction) Homework Equations F = kq/r^2 k = 9x10^9 The Attempt at a Solution Using that formula, I calculated q1 to equal -45kN and q2 to...