# Search results

1. ### Getting sick during term

Hello all, How exactly do you all cope with getting sick during a school term? For example, if you were to have a flu? Do you continue studying, or do you take a break to get well? I have been doing absolutely nothing these last two days because my head won't let me. I did however finish a math...
2. ### Maximizing volume

Homework Statement Canada Post accepts international parcels whose (Length+Girth) is less than or equal to 2 meters, and Length is less than or equal to 1 meter. Girth is defined as the cross section. We wish to ship a parcel of the shape of a triangular prism of length l meters. The cross...
3. ### Rms voltage for capacitor charge/discharge

Homework Statement Hello, I was wondering if anyone could confirm my work for the following graph: I'm supposed to find the rms for 1 complete cycle (0, 10ms) The time constant is 1ms. Charging phase, v=1-e^(-t/1ms)=1-e^(-1000t) discharging phase, v=e^(-1000t) The Attempt at a...
4. ### Average of 2 functions

Homework Statement My question pertains to taking the average over a particular period that is composed of 2 functions. For example, from [0, 5ms] the function is defined by 1-e^(-t/1ms)and then by e^(-t/1ms) from [5ms, 10ms]. Will the average from 0-->10 simply be the following...

Homework Statement Hello all, I encountered this practice problem for my midterm tomorrow involving the gradient operation. Let (r, θ) denote the polar coordinates and (x, y) denote the cartesian coordinates of a point P in the plane. A function is defined via f(P)=xsinθ away from the origin...
6. ### Zener Diode Analysis

Homework Statement A zener diode D1 is specified to have Vz=3.8V and a knee current of 100 microamps. It is used as a shunt regulator where the minimum load resistance is 6.2k. What is the minimum power source that ensures that the shunt regulator remains regulated? Homework Equations...
7. ### Using differential nad linear approximation

Homework Statement I just have a question regarding "estimating" the value of a function at a given point. Say we have a function f(x, y, z, w) and we want to know the value of that function at f(1.99, 1.001, 8.02, 2.01) Can we simply do the following: let f=f(2, 1, 8, 2) and...
8. ### Motional emf

Homework Statement Here is the picture: I have an upcoming test, and I cannot seem to get any questions like this one. Help is greatly appreciated. I calculated the net force, such that Fnet=ma. There exists a magnetic force due to the current in the wire. The mass m is negligible, ie...
9. ### Bar and rail in magnetic field

Homework Statement Couple questions regarding the following image: What is meant when the problem states that "steady state can be achieved"? Will current be induced in this set up due to the acceleration to the right? For example, would I go Fg1-Fg2-Ffriction= Fmagnetic, and from there...
10. ### Time constant for capacitors and for inductors

Homework Statement Quick question. If you were to find the Thevenin's equivalent circuit between the terminals of an inductor, and thus calculated the time constant using Rth, would the time constant be same as if you were to not? Same question for capacitor circuits
11. ### Engineering Circuit Analysis Involving Inductance

Homework Statement The Attempt at a Solution Just was hoping someone here would be able to help me with the circuit above. I wanted to ensure that I analyzed it properly. I applied Ohm's Law to determine the initial current through the inductor. i(initial)=-16V/2.2kΩ=-7.27 mA...
12. ### Textbook Suggestion: Electromagnetism

Hello all, I'm looking for some suggestions for textbooks regarding electromagnetism. I want something that goes in depth and really provides the concepts required to actually understand electricity and magnetism. Any Electrical Courses that I am taking are all circuit analysis.... Regards, D...
13. ### Programs Computer Engineering to Electrical w/Minor in Physics

Hello all, I was considering switching from my current degree of Computer Engineering to Electrical Engineering with a Minor in Physics (with a focus on materials science). Reason for the switch is I am much more interested in the hardware of electronic devices, as opposed to the software...
14. ### If we know the inductance of an iron-cored coil to be 200mH, and we

If we know the inductance of an iron-cored coil to be 200mH, and we remove the iron core such that the core is now air, how exactly can we determine what the new inductance is with just this information? I played around with the equation for inductance, however, I could not seem to get it...
15. ### Curvature and Torsion

Homework Statement http://www.mathhelpforum.com/math-help/attachments/f6/22423d1317129472-curvature-torsion-untitled.png [Broken] The Attempt at a Solution What I did was I calculated the unit vector for dN/ds={.21i+0.91j-0.42k}/ sqrt(.21^2+.91^2+0.42^2)=.205i+0.889j-.4102k...
16. ### Torque on a current carrying wire

Homework Statement Consider the 20cm square loop of rigid wire shown in the figure. The wire has a diameter of 3mm and is lying flat on a table made of paramagnetic material. A uniform magnetic field of B=0.6 rans parallel to the table top as pictured. Electrical connection to the thick...
17. ### Recomendations for Introductory Circuit Analysis Textbooks

As the title states, I am looking for recomendations, and explanations as to why it was a good book. Some current suggestions I have had is by Robert L. Boylestad. Thanks in advance!
18. ### Integration application, force due to fluid pressure

Homework Statement I'm working on a particular problem that involves the force on a face of a triangular prism under water. What I am wondering is if someone could explain how to find dA for the prism? If the prism is an equilateral triangle, then dA=\sqrt3dy doesn't it? My book is showing...
19. ### Mass, Moments and Center of Mass

Homework Statement A square plate with edge a cm and areal density kr g/cm^2, where r is the distance (in centimetres) from P to one of the diagnals of the square. Find the mass. The Attempt at a Solution I know my diagram is wrong, and I know what the correct one looks like. However, I...
20. ### Thevenine Equivalents

So for each of the figures I want to find the Thevinin equivalent resistance and voltage. I also want to find the maximum power dissipated by a load resistor placed between points a and b on all three figures. Finally, I want to know what Vab is when a 7-olm resistor is placed between a and b...
21. ### Questions involving more than one voltage source

Consider the following circuit. Using superposition determine a) the magnitude and b) the direction of the current going through R_1 (is it away from node a?). Dtermine the c) magnitude and d) direction of the current through R_2 (is it away from node b?). e) Find V_{ab}. a) First, I will...
22. ### Current and voltage sources

Homework Statement Find the current through the resistor R1. The Attempt at a Solution First I short circuited the voltage source and determined I1. I1=(9A)(10-olms/18-olms)=5 A down Next, I short circuited the current source and determined the current going through R1 via olms...
23. ### Cleaning up circuit diagrams

Homework Statement Essentially I am pursuing clues as to what I should do in order to clean up the following circuit: . I'm kind of confused regarding the portion where it says "no contact". Help?
24. ### Circuit with just a battery and ground

What would happen if you just hook up a battery to itself, and a ground? I understand resistance is negligible in wires when there are other resistors, however, this doesn't seem to be the case when this occurs. But what happens? Battery drains extremely fast ?
25. ### Work (conceptual)

I have found that I only need to brush up on my coceptual grasp of work and electrical applications. I have found that I am having negative answers when indeed the answer is positive. My question to you is, if I am following q(Vb-Va)=-W, I am assuming this is the work done by the field, and the...
26. ### Phototubes, Voltage

Homework Statement The Attempt at a Solution What I am wondering is if I found all of the answers for figure 1, wouldn't I just be repeating those same answers for figure 2 and 3? Or is the way it arranged important? Here are the values I found: Vc1=1.51V Vc2=1.61V Vc1c2=-0.1V...
27. ### If the electron is freed up, what would be its acceleration?

Homework Statement The Electric Potential on an XY plane is described by the relationship V=2x^2-2y^2. Consider ONLY values in the range [0, 5]. A) Depict on an XY plane three lines of equal potential V=-4V, 0V and 4V. Consider 5 ponts. X= 0, 1, 2, 3, 4, 5. B) Consider one point where x=...
28. ### Integration by Parts

Homework Statement \intx^2tan^{-1}xdx The Attempt at a Solution \int{x^2tan^{-1}xdx} \int{x^2tan^{-1}xdx} = \frac{x^3}{3}tan^{-1}x-{\frac{1}{3}}\int \frac {x^3}{1+x^2}dx let {}u=1+x^2, \frac{du}{2}=xdx \frac{x^3}{3}tan^{-1}x- \frac{1}{6}\int (1-1/u)...
29. ### Electric Field and Uniformly Charged Planes (conceptual)

Homework Statement I am pursuing conceptual help regarding electric field due to uniformly charged planes. Homework Equations E=\frac{\sigma}{2\epsilon} The Attempt at a Solution I understand that a capictor has plates that are +/-Q. However, how would you calculate the elctric...
30. ### Conductors in Electrostatic Equilibrium problem

Homework Statement In fair weather, over flat ground, there is a downward electric field of about 150 N/C. A) assume that the Earth is a conducting sphere with charge on its surface. If the electric field just outside is 150 N/C pointing radially inwards, calculate the total charge on the...