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Ohm's Law

Find Resistance

In the ohmmeter circuit shown, the voltage drop across the ammeter and the internal resistance of the 1.5V battery are negligible. The variable resistor R is adjusted to give full-scale deflection of the micoammeter when R_x is zero. Find the numerical value of R. (See attachment for diagram)

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

Physics: 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?

Gain and Output Voltage

For the following operational amplifier circuits, find the gain and output voltage theoretically: a) Non-Inverting Amplifier Circuit (see attached file Non-Inverting Amplifier.jpg) b) Voltage Follower Amplifier Circuit (see attached file Voltage Follower Amplifier.jpg) c) Inverting Amplifier Circuit (see attached file Inver

How much current will be flowing through the circuit?

A capacitor has capacitance 4 microC/Volt. It is placed in series with a resistance of 48 Ohms and 25 volt source. When the current in the circuit has built a charge of 67 microC on the capacitor, how much current will be flowing through the circuit?

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


Ten volts are applied across points a and b depicted in the figure. (Ignore the resistance in the wire.) What is the current in the 12 ohm resistor?

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?

Lightbulb resistance and efficiency

A GE Softwhite lightbulb is rated as follows: rated power = 60 W ; rated optical power = 820 lumens (lm) 1 lm = 1/680 W operating life = 1.5 h rated operating voltage = 115 V The resistance of the filament of the bulb, measured with a standard multimeter is 16.7 ohms. When the bulb is connected into a circuit and is

Do any of the bulbs have a complete circuit when all the switches are open?

1. Consider the circuit shown in the attachment. a. Do any of the bulbs have a complete circuit when all the switches are open? Which one(s)? b. Do any of the switches cause a short circuit when closed? Which one(s)? c. Which switches should be kept open, and which should be closed for the following to occur? * only bulbs A


1. See attachment. 2. See attachment. 3. Three resistors are connected in series. Then they are connected in parallel. In which configuration will the resistance be greatest? a. series b. parallel c. It won't make any difference 4. See attachment. 5. See attachment.

What is the resistance?

1. An ammeter registers 2.5 A of current in a wire that is connected to a 9.0 V battery. What is the wire's resistance? 2. A small electronic device is rated at 0.25 W when connected to 120 V. What is the resistance of this device?

Calculating Internal Resistance

Question: A 1.40 ohm resistor is connected across a 9.00-V battery. The voltage between the terminals of the battery is observed to be only 8.00 V. Find the internal resistance of the battery. Make sure the answer is in Ohms.

Working with Resistor Networks

The resistance of the first device is 12 ohms, the resistance of the second device is 4 ohms, and the voltage developed by the generator is 40 V. What is the magnitude of the current flowing through the first device? (a) 3.33 A (b) 8A (c)10A or (d) 13.32A

Electric circuit

If the resistance of an electric circuit is 12 ohms and the voltage in the circuit is 60 V, the current flowing through the circuit is?(A) 0.2A (b)5 A (c)60Aor (D) 720A.

Mixed Circuit

Find all the currents and potential differences in the following circuit.

Working with the variation of resistance in regards to temperature.

(a) A 5 m length of copper wire at 20°C has a radius of 0.25mm. If a potential difference of 10V is applied across the length of the wire, determine the current in the wire. (b) If the wire is heated to 50.0°C and the 10 V potential difference is maintained, what is the resulting current in the wire?