Because it reaches the end of the line every half cycle! Electricity flows at approximately the speed of light.
This is incorrect. Electrons in the wire actually move at a very slow speed (about 0.0001 m/s, or 0.00022 mph), and this speed is called the drift velocity of the electrons. However, this is neither here nor there in regards to the question. Current is defined as the rate of flow of charge, or I = q / t, where I is the current, q is the net charge, and t is the net time. Each electron has a small charge, and in an AC current the each electron oscillates back and forth about a single point in the wire. Our definition of current as been fulfilled: we have charge flowing. It makes no difference that the electrons are simply moving back and forth; they are still moving. It's an interesting thing to note that the power company doesn't actually provide you with charge; all they do is the work required to move the charges already in your wires back and forth.
reversing the voltage no current flow until breackdown
The reversing valve
A diode is a semiconductor meaning it will conduct from anode to cathode if the anode is held positive. Reversing the polarity Will in effect block current flow.
A Counter-current flow has more advantages as comapared to a co-current flow.
The diode is a unidirectional device it allows current to pass through it only when it is forward biased and does not allow when reverse biased when ac signal is supplied in the positive half cycle of the ac wave signal the diode will b in forward biase n in the negative half cycle it is in reverse bias .Hence it allows only the positive half cycle current to flow through it the resultant wave form will b only in one direction ,i.e,dc signal with ripples. only half of the wave is rectified hence it acts as a half wave rectifier
reversing the voltage no current flow until breackdown
Reversing the current flow in an electromagnet changes the direction of the magnetic field it produces. This can be useful for changing the polarity of the electromagnet or controlling the direction of a mechanical system it is used in.
A device that changes the direction of the current is called a "switch" or a "reversing switch." This device allows for the current to flow in different directions as needed.
The reversing valve
In an AC circuit, the direction of current alternates back and forth periodically. This means that the current flows in one direction for a period of time and then reverses its direction, completing one cycle. This back-and-forth movement of current is what allows electrical devices to operate consistently and efficiently.
The polarity of an electromagnet is determined by the direction of the electric current flowing through the wire coil. Reversing the direction of the current will change the polarity of the electromagnet.
A diode is a semiconductor meaning it will conduct from anode to cathode if the anode is held positive. Reversing the polarity Will in effect block current flow.
A diode is a semiconductor meaning it will conduct from anode to cathode if the anode is held positive. Reversing the polarity Will in effect block current flow.
A diode is a semiconductor meaning it will conduct from anode to cathode if the anode is held positive. Reversing the polarity Will in effect block current flow.
A flow of electric current creates a surrounding swath of magnetic flux. This flux will mingle with and surround the current flow. If the current is bent by say winding a wire in the form of a coil, the flux will shape itself around the coil. The strength of the flux will vary with the current. Reversing the current reverses the flux direction.
A solenoid in a dishwasher controls the flow of water by using an electric current to open and close a valve. When the dishwasher is in the washing cycle, the solenoid is activated to allow water to flow into the dishwasher. When the cycle is complete, the solenoid closes the valve to stop the flow of water.
A woman has her menstrual flow during menstruation, which is at the start of her menstrual cycle. The typical menstrual cycle is around 28 days, meaning she should menstruate roughly every month.