What exactly is voltage? - Electrical Engineering Stack Exchange
What is voltage? It's a stack of invisible membranes which fill the space between charged capacitor plates. Voltage is the pattern of concentric onion-layers which surround any charged object, with the onion-layers running perpendicular to the flux-lines of the electric field. So, 'stacks of voltage-layers' is one way of describing an electric ...
voltage - How to find the power of each individual bulb in a 50 …
2024年12月28日 · Voltage Drop: I calculated the voltage drop using this formula: V = 240 - I (total) × R (wires) But I didn't quite get the hang of it, I couldn't get the total current (I) in the circuit. Power Delivered: P = V^2 / R. I couldn't figure out the current through the circuit and there is no diagram of the circuit given.
How are current and voltage related to torque and speed of a …
2012年9月3日 · A DC motor can be approximated as a circuit with a resistor, and voltage back-emf source. The resistor models the intrinsic resistance of the motor windings. The back-emf models the voltage generated by the moving electric current in the magnetic field (basically a DC electric motor can function as a generator).
Understanding voltage levels on 3.5 mm audio output
2017年4月9日 · When no audio is playing, there's a voltage of about 2 mV. When I output a constant audio signal, the voltage rises initially to 0.5 V, but drops back to 2 mV after 2-3 seconds. What purpose does this 2 mV bias voltage serve? Does audio output circuitry usually contain DC blocking capacitors, or is DC blocked via some other means?
How much voltage/current is "dangerous"? - Electrical Engineering …
Likewise, if the current and voltage are below a certain level, a person can--given enough time--safely absorb an arbitrarily large amount of electrical energy. Further, if voltage is sufficiently low, the amount of current that can flow as a consequence of such voltage will be too low to cause harm. \$\endgroup\$ –
voltage - Is power proportional to V or V^2? - Electrical …
2021年1月20日 · If the resistance is constant, then increasing the voltage increases the current proportionally, exactly proportionally in the ideal case. Power is not proportional to voltage squared in cases where the load is not a constant resistance. For example, with a rectifier diode it will increase considerably faster than voltage squared.
voltage - Why does USB have Vcc=5V and high=3.3V? - Electrical ...
2015年9月15日 · The higher voltage allows compensation for voltage drop to the device. If USB was 3.3v then if you had a long cable and poor connectors with 0.5v of drop then the device will only run at 2.8v. If the voltage is 5v the you still have 4.5v to work with and that is enough to run an LDO voltage regulator.
voltage - How does data travel inside a wire? - Electrical …
Current and voltage are inseperable. The current is flowing because there is a voltage on the wire, and there is a conductive path from that voltage to a lower voltage. So we can say the data is encoded as voltage pulses or current pulses, it doesn't really matter. Often a high voltage (5 V) indicates a "1" and a low voltage (0 V) indicates a "0".
What is "forward" and "reverse" voltage when working with diodes?
2011年3月3日 · The reverse voltage is the voltage drop across the diode if the voltage at the cathode is more positive than the voltage at the anode (if you connect + to the cathode). This is usually much higher than the forward voltage. As with forward voltage, a current will flow if the connected voltage exceeds this value. This is called a "breakdown".
What is the voltage range of a standard headphone jack from a …
Depending on what the functional goal is, there's likely to be enough voltage swing to measure substantial differences with the Arduino's ADC, or even digitally threshold for an NRZ protocol. However, yes, for highest analog fidelity a pre-amp could well be needed to utilize the entire ADC range, and is probably cheaper or at least easier to ...