DC is a current that flows from a higher potential source to a lower potential load in a positive to negative direction. The alternating current is unidirectional. It changes the direction several times according to the frequency of the power source.
What is the difference between AC and DC currents?
Considering the fact that both alternating and direct currents with their associated voltages are used to transfer energy over time to do something useful for humanity, we consider analogies that contain the dissimilarity between alternating and direct current. Imagine, we want to build a vehicle that drives through a medium such as water or air.
We have some options, but we limit the functions to the two most common ones. one. Since nature has never developed a fully rotating joint, all its movements are the oscillating projection of a rotation and therefore contain only the oscillating or undulating forms. All fins of fish and whales and wings of flying creatures swing back and forth to impart energy, and the creature moves forward with air or water currents through an oscillating or undulating or alternating cycle.
This action involves double-acting pistons in steam engines and alternating magnet systems as alternators and transformers. b. For ships and boats, the propeller turns completely in one direction, with one tip running in one direction while the other tip returns. However, the two peaks always move in the same direction without oscillation, and yet the sea or air vehicle is moving at this constant forward propeller speed.
Belt and chain drives as well as water cooling in cars, cooling circuits and DC generators use such principles of unidirectional flow. With some ingenuity, one can correlate the AC and DC currents and the associated voltages to use two types of tools for demolishing a wall. You can apply a PERMANENT pressure in one of the directions (+ or -) to tear down the wall, or you can apply repetitive VIBRATIONS and shake them apart. Both methods transfer energy to destroy the wall. It is so interesting that nature has preferred AC waves to drive most limbs of living things and plants without requiring a fully rotatable joint.
In fact, some wind generators now use vortex shedding to vibrate a long pole rather than turning a turbine in one direction. Nature did it all long before Nikola Tesla through AC. It may be said that DC is a three-dimensional rotating system in which the tips of a radial arm always move in one direction, while AC is the projection of the three-dimensional DC system on a flat plane leading to the sinusoidal or cosinusoidal projection of the alternating current leads.
They could be called the same, but one is a three-dimensional motion, so a steady flow is possible, but the AC is a flat projection of a three-dimensional function, and therefore oscillates on a flat plane!
What is the main difference between AC and DC current and voltage?
AC voltage is an AC voltage. The AC waveform starts at zero, reaches the positive peak, and then reaches zero. When the zero value is reached, the waveform reaches the negative peak and returns to zero. This is the one full cycle of alternating current. When we speak of 50 Hz AC, the waveform has a positive value for 10 ms and a negative value for 10 ms. Thus, the total duration is 20 ms. The AC waveform changes the direction periodically.
When the AC voltage is applied to the load, the AC current flows in the circuit.
Unlike AC, the DC voltage is unidirectional and can have either a positive or a negative value. The waveform does not change with time.