Share
Explore BrainMass

# Ohm's Law

### Derivatives to Calculate the Rate of Change

The voltage, V, (in volts) across a circuit is given by Ohm's law: V = IR, where I is the current (in amps) flowing through the circuit and R is the resistance (in ohms). If we place two circuits, with resistance R1 and R2, in parallel, then their combined resistance, R, is given by 1/R = 1/R_1 + 1/R_2 Suppose the current is

### A Bird Sitting on a Power Line: The Difference between its Feet

A bird sits on a high voltage power line with its feet 2.0 cm apart. The wire is made of aluminum, is 2.0 cm in diameter and carries a current of 150 A. What is the potential difference between the bird's feet?

### Current and voltage supplied by battery

A battery with E=10V and internal resistance r= 1kohms is connected to a simple circuit with a total resistance of R=9kohms 1.)What is the current through the battery. 2.)What is the potential difference between the battery's terminals. 3.)How much power does the battery supply to the simple ciruit. 4.)How much power

### Capacitive of resistor is connected in series

A 250Ω resistor is connected in series with a 480µF capacitor. The voltage across the capacitor is VC = 7.6V sin [(120 rad s−1)t] i) Determine the capacitive reactance of the capacitor. ii) Derive an expression for the voltage VR across the resistor.

### Management Presentation MIS

Management Presentation assistance - CHD Meridian Healthcare, Inc.

### electric field in a current carrying wire

A cylindrical tungsten filament 15 cm long with a diameter of 1.0 mm is carrying a current of 12.5A an it is to be used in an environment with changing ambient temperature (from 20 to 120C). What is the maximal electric field in the wire. What is the resistance? What will be the maximal potential drop?

### Thermal Coefficient of Resistance

A 1.70 m cylindrical rod of diameter 0.450 cm is connected to a power supply that maintains a constant potential difference of 15.0 V across its ends, while an ammeter measures the current through it. You observe that at room temperature (20.0 degree Celsius ) the ammeter reads 18.7A , while at 92.0 degree Celsius it reads 1

### Electric Circuit Calculations of Impedance, Phase Angle and Magnitude

A p.d. of 60 Vrms is connected between terminals A and B in the network below. See attachment for diagram. For a frequency of 50 Hz calculate: a. The J notation impedance of the network b. The phase angle c. The magnitude of the voltage across R1 and its phase angle relative to the supply voltage.

### power supply and sensor

A power supply outputs 24VDC at 3A. I have a sensor that needs 24VDC at 100mA. If I do ohms law V/I = R I then do 24VDC/100mA and get 240 for resistance. My wire will go from the supply terminal block through a series wire then a resistor to my sensor. Will this method at 240 ohms reduce my current to 100mA from 3A. If not

### Reducing power losses in transmission of alternating currents.

I know V=IR, P=IV, P=I^2R and P lost = I^2R. Here problem....Told like in an AC distribution system like a power grid when voltage increased current is decreased where R is constant over the power lines. If current were increased voltage would decrease. These equations above plotted numbers to prove , which is what is really

### Series RL Circuit

The problem is in the right column of the attached page. There are two # 11's so it is the one on the right. See attached file for full problem description. You have a 200 ohms resistor, a 0.400 H inductor, and a 6.00 uF capacitor. Suppose you take the resistor and inductor and make a series circuit with a voltage source th

### Resistance Between Electrodes

A square film of Nichrome, an alloy of nickel and chromium, has copper electrodes deposited on two opposite edges. Show that the resistance between the electrodes depends only on the thickness of the film on its conductivity, as long as the film is square. This surface resistance is expressed in ohms per square.

### Circuit Analysis Applied to Membrane

In a certain neuron, the action of a synapse can be represented as in the figure below. The cell membrane resistance is 2Mohm and the reversal potential of the rest of the EPSP is 30mV above the resting potential of the cell. If a microelectrode records the EPSP as 5mV of depolarization (assume steady state), what was the effect

### Basic questions on Ohm's law, Kirchhoff's laws.

Please only do review questions 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 2.10 and problems 2.2, 2.3, 2.4,2.5, and 2.6.

### Modeling with first order Differential Equations (Five Problems).

9. When a vertical beam of light passes through a transparent medium, the rate at which its intensity I decreases is proportional to I(t). where t represents the thickness of the medium (in feet). In clear seawater, the intensity 3 feet below the surface is 25% of the initial intensity Jo of the incident beam. What is the intens

### Three problems on circuit analysis.

Please solve problems 26.60, 26.62, and 26.64. See attached file for full problem description.

### Series circuit of a resistor, inductor and capacitor

(See attached file for full problem description) You have a 200 ohm resistor, a 0.400-H inductor, and a 6.00 -muF capacitor. Suppose you take the resistor and inductor and make a series circuit with a voltage source that has voltage amplitude 30.0 V and an angular frequency of 250 rad/s. a) What is the impedance of the ci

### Impedance and Resonance Frequency of a Circuit

Consider a series RLC circuit with R=15 ohm, L=200mH,C=75uf, and a maximum voltage of 150V. a) What is the impedance of the circuit at resonance? b) What is the resonance frequency of the circuit? c) When will the current be greatest - at resonance, at 10 percent below the resonant frequency, or at 10 percent above the reson

### Voltage Divider Circuit

The voltage divider network of Figure 2.37 (attached file) is expected to provide 5 V at the output. The resistors, however, may not be exactly the same; that is, their tolerances are such that the resistances may not be exactly 5 k&#937;. a) If the resistors have ± 10 percent tolerance, find the worst-case output voltages.

### Application of Faraday's law of electromagnetic induction

(See attached file for full problem description with proper symbols and diagrams) --- 1. How fast would you have to move a 1.0 m long conductor to produce a motional emf of 1.0 V in a 4 x 10^ -4 T magnetic field (assume that the conductor moves perpendicular to the field)? If a resistance of 0.5 ohm is co

### Current in Resistor - which terminal will be positive?

Refer to attached picture). There is a current of 10.0 amperes initially in the long straight wire shown at the bottom of the following diagram produces a flux of 0.0511 webers in the single loop circuit containing the resistor. If the current in the long straight wire is uniformly reduced to ¼ of its original value in 1.99

### Calculating maximum voltage, current and energy

Please help with the following problem. Step by step calculations are given. An L-C circuit consists of a 60.0 mH inductor and 250 µF capacitor. The initial Charge in the capacitor is 6.00 µC and initial current in the inductor is zero. a) What is the maximum voltage across the capacitor? b) What is the maximum current

### Working with inductors - but connected to a battery

1. An inductor is connected to the terminals of a battery that has an emf of 12.0V and negligible internal resistance. The current is 4.86mA at 0.725 ms after the connections is completed. After a long time the current is 6.45 mA. What is a) The resistance R of the inductor? b) The inductance L of the inductor?

### Electric Resistance and Ohm's Law

A bird lands on a bare copper wire carrying a current of 32 A. The wire is 8 gauge, which means that its cross-sectional area is 0.13 cm^2. (a) Find the difference in potential between the bird's feet, assuming they are separated by a distance of 6.0 cm. (b) Will your answer to part (a) increase or decrease if the separation

### Electric Circuits

1) For the circuit below find: a) The current through R1. b) The current through R2. c) The current at the ammeter. See attached file for full problem description.

### Transfer Function

Find the transfer function IL/Vs for the following circuit in the attached file.

### Circuit Analysis

Refer to the following circuit. Assume ideal voltage source - find VBG and I2

### Efficiency of electrolysis (in joules).

The amount of product produced by electrolysis is limited by Faraday's law. Therefore, as I understand it, the amount of product produced depends on the amps rather than on the volts (although the minimum voltage for a given reaction plus overvoltage must be met). For example, lets say you have a reaction that requires at

### Voltage Drop Across the Resistor

Determine the voltage drop (from top to bottom) across the 16 ohm resistor in the circuit shown. Determine the voltage drop across the 4 ohm resistor. What is the voltage V?