Explore BrainMass


Regulation of power supply & Gains of CE amplifier

1) A power supply produces 24 volts at full load with a percent regulation of 10%, calculate the no-load voltage of the supply. 2) A common- emitter transistor amplifier has a base current change of 15 microamperes and a collector current change of 200 microamperes. The load resistance is 50000 ohms withan input resistance of

A Current Though A Voltage AC Source

Consider a circuit in which a capacitor and an inductor are connected in parallel to an AC source. Which of the following statements about the magnitude of the current through the voltage source is true? It is always larger than the sum of the magnitudes of the currents in the capacitor and inductor. It is always less t

Magnetic forces on a current carrying triangular loop

The triangular loop of wire shown in the drawing carries a current of I = 4.70 A. A uniform magnetic field is directed parallel to side AB of the triangle and has a magnitude of 1.80 T. (a) Find the magnitude and direction of the magnetic force exerted on each side of the triangle. (b) Determine the magnitude of the net fo

Current Drawn by a Triangular Array of Resistors

A triangular array of resistors is shown in the figure (see attachment). What current will this array draw from a 30.0V battery having negligible internal resistance if we connect it across (a) ab, (b) bc, (c) ac?

Break-even points

Needs assistance in completing spreadsheet for break-even points. ? Calculate the break-even points (at various price levels) and the operating leverage for the software and keyboard divisions. State and explain the assumptions you made when performing these calculations. ? Describe how the break-even quantities and operat

Uninterrupted power supply

For a computer system you can access, determine how much wattage output a UPS should have in the event of a total blackout, and estimate how long the UPS should sustain power. Research the market and report on the features and prices of a standby UPS and an inline UPS. Include the following information in your answer: Wattag

LCR Circuit - finding currents and voltage

In the circuit below, V is an alternating voltage of a constant amplitude 10 V but of variable frequency. The purpose of the circuit is to detect a frequency of 1600 Hz by operating the relay. CT is a 2-to-22 nF trimming capacitor used to adjust the resonant frequency of the circuit. This is set to 10 nF. Calculate the maxi

Voltage, Impedance, Capacity and Inductance.

See attached file for full problem description. 1. An ac voltage at 1000 Hz is applied to a resistor and an inductor in series. The rms current in this circuit is 0.600 A. if the impedance of this circuit is 110 ohms, what is the maximum value of the voltage. 2. A 200- ohm resistor, a 40.0 mH inductor and a 2.00 uF capacitor

Electromagnetism: LCR circuits, Phasors, Torque on a coil.

See attached file for full problem description. 9 (a) Sketch the Phasor diagram for an ac circuit with a 108 omega resistor in series with a 25.5 mH inductor and a 34.7 mu F capacitor. The frequency of the generator is 60.0 Hz. (b) If the rms voltage of the generator is 120 V, what is the average power consumed by the circuit

series RL circuit..

See attached file for full problem description. 14. The inductive reactance of a 20 mH inductor at a certain frequency is 120 ohms. What is the frequency in rad/s? 15. A 100-ohm resistor is connected in series with a 10 mH inductor across an ac source operating at 1000 Hz. What is the impedance of the circuit? 16. The p

AC/DC Circuits

1) AC and DC: a) If have a DC circuit must use current limiting resistors on all loads that are dc so will not blow the dc parts up. b) If an AC circuit you do not need to worry about current limiting resistors cause motors and coils, and transformers that use AC only consume what current they need when run and do not blow

Complex Power and Impedance of a Load

An electrical load operates at 240 Volts rms. The load absorbs an average power of 8 kW at a lagging power factor of 0.8. a) Calculate the complex power of the load. b) Calculate the impedance of the load. a) S(L)= 6+j8 kVA; b) Z=5.76 e^(-j36.87degrees)OHMS b) S(L)= 8+j6 kVA; b) Z=5.76 e^(j36.87degrees)OHMS c) S(L)= 8+j

Circuit analysis problem

Question 1. (16 Points, 2 pts each) a. Which is better for transmission of electric power over long distances: DC low voltage or AC high? b. Where in the Washington DC area is there a statue of Joseph Henry c. What is the SI (MKS) unit of inductance? d. Write an equation for the terminal relationship for an inductor? e.

RC series circuit problem

Problem 6. Consider the simple circuit shown below. The voltage source provides V1(t) = 100 cos (wt) Volts. a) Define reference directions for voltages and currents. b) Write down a complete set of linearly independent equations for the phasor quantities in this circuit. c) Solve these equations to find the expressions fo

25 Multiple choice questions based on alternating current and EM waves.

(See attached file for full problem description) --- 1. The current in a certain ac circuit is independent of the frequency at a given voltage. Which combination of elements is most likely to comprise the circuit? a. Resistors only b. Inductors only c. Capacitors only d. A combination of inductors and resistors e. A c

Capacitance of the Capacitor Scenarios

Here are some problems I have some answers but just want to make sure they are correct but I have some other questions where I am just lost in trying to figure out! 1.)Three capacitors of 5, 10, and 15 microfarads are connected in series. Potential difference across the capacitor network is 25v. a.) what is the equivalent ca

Electromagnetic Induction

1.) Okay I have this problems but I can't get the picture or show the picture so i will describe it. I have two loops or circles next to each other. The first loop is continuous and there are no breaks in the loop. So it looks just like a circle. The second loop has a break in it and it also has a emf or power supply then it

RL Circuit Inductor Connected

The rms current in an RL circuit is 0.30 A when it is connected to an ac generator with a frequency of 60.0 Hz and an rms voltage of 25 V. (a) Given that the inductor has an inductance of 140 mH, what is the resistance of the resistor? (ohm) (b) Find the rms voltage across the resistor. (V) (c) Find the rms voltage ac

Diodes and Path of Current

Sketch the path of the current through the diodes when the voltage is as given for the two cases shown (see attached file for full problem description). If the voltage drops across each diode is 0.7V, what is the current through the resistor in each case? Finally, use the bridge circuit shown and design a DC power supply for a 1

Capacitors and derivations, RC circuits

Please see the attached files for full problem descriptions. I am confused on specific calculations only. the derivations. scan003.jpg part 1 a). the derivation scan003.jpg part 1 c). the derivation scan0004.jpg a). the derivation Please include as many steps as possible so I can understand the process.

AC-LCR Circuits: Inductance, Capacitance and Frequency

Given 10V ac source, LCR series circuit, Imax at resonance=2 A; f= 200Hz Imax = 1.2A; f=350Hz Imax = 1.5A Given these parameters what is the resonant frequency and how did you get this value? What is L and C in the series circuit? Given these values what is the phase angle at f=250Hz?

LRC series circuit

Given 10Vmax ac source, LRC series circuit, Imax at resonance frequency Imax=2A; f= 200Hz; Imax = 1.2A; f=350Hz Imax = 1.5A What equations are used and how are the values found? What is the resonant freq and the phase angle at 250Hz?

Given an RL circuit, find the rms voltage and current.

7. An RL circuit consists of a resistor R = 63 ohms , an inductor, L = 45 mH, and an ac generator with a rms voltage of 120 V. (a) At what frequency will the rms current in this circuit be 1.5 A? (b) For this frequency, what is the rms voltage across the resistor, Vrms,R? (c) For this frequency, what

AC Circuit

4. The maximum current in a 21 µF capacitor connected to an ac generator with a frequency of 120 Hz is 0.12 A. (a) What is the maximum voltage of the generator? V (b) What is the voltage across the capacitor when the current in the circuit is 0.10 A and increasing? V (c) What is the voltage across the capacitor wh

Solving: Transformers

Please provide some assistance with the following problem on transformers. Please discuss the mode of action of a transformer, step-up vs step-down transformers and the number of turns in the primary winding. Please view the attachment file for the full problem and figure.

Kirchoff's Rules Explanation

This is a question about Kirchoff's rules. Consider the group of resistors shown in the attachment, where R1 = 4.0 ohms and E = 9.1 V. Find the current in each resistor. And determine the potential difference between points A and B. Please see attached for diagram.

AC Generator

We have a AC generator that is attached to a resistor with 500 kohms and a maximum voltage of 90 V. How do you calculate Imax, max power, avg power, rms current, rms voltage, and frequency.

Induction of a current in a wire

A magnetic field is perpendicular to the plane of a single-turn circular coil. The magnitude of the field is changing, so that an emf of 0.84 V and a current of 3.7 A are induced in the coil. The wire is the re-formed into a single-turn square coil, which is used in the same magnetic field (again perpendicular to the plane of th