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television antennae
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Does the metal need to be an certain size or length for an electromagnet?
You can make any metal piece of any size an electromagnet by wounding a conducting wire around it and passing an electric current through it....
How does the resistance of a wire vary with its length?
resistance of wire increases with increases of length
Is wire an insulator or conductor?
A metal wire is a conductor. It is the plastic layer round the wire that is an insulator.
What is the word for the meaning 'a flexible strand of metal'?
flexible strand of metal = wire
How does the resistance of a wire vary with its lenght?
If the wire's cross-section area is constant, then its resistance per unit length is constant, and the total resistance should be directly proportional to the length of a wire segment.
What is an Grade an answer to what affects the resistance in a wire?
*the resistivity of the metal the wire is made of *thickness of wire *length of wire
What is the resistance of metal wire?
the resistance is depends on the type of the metal and ith length
What length of wire of diameter 1mm can be made from a 1cm cube of metal?
Approximately 127 cm length of a wire with a diameter of 1mm can be used to make a 1cm cube of metal.
Is bending a metal wire a chemial or phyiscal change?
Physical. The metal wire is still a metal wire after the change.
What is the need for antennas what are transmitting antennas what are receiving antennas?
Antennas transfer energy from a cable into the airwaves efficiently. Any transmit antenna can also be a receive antenna and viceversa. If you wish to transmit high power from an antenna, usually heat generation or high voltage is a concern that can destroy the antenna. To prevent problems, high power antennas require thicker wires and sometimes insulators to prevent overheating/burning and arcing. Many antennas can simply be made of wire of a simple length and they'll be very efficient. The length of an antenna changes it's efficiency to the cable. If you want the antenna to be efficient, you must size it to match the cable impedance. Usually the length of a single wire exiting above a metal plate is one quarter wavelength or 1/4 x 11,803/frequency in megahertz. For FM radio on an automobile, some antennas have motors that extend out of the body of the car. The height (inches) should be 1/4 x 11,803/100 megahertz or just under 30 inches. TV antennas above a house are most often a set of half wavelength wires, so change the 1/4 to 1/2 in the formula above. They use many different wire lengths to cover all the frequencies in the television band, which extends from about 50 megahertz to around 600 megahertz. Cell phone frequencies were picked partly to make the antennas small and partly so that cell phone reception can enter buildings with rebar reinforcement. Cell phone frequencies are roughly 800 megahertz and 1800 megahertz. Receiver antennas are often made smaller than either transmit or transceiver antennas. If you open up the back of an older transistor radio, you are likely to find a bar made of ferrite material with an insulator and wire wrapped around that. The wire is wrapped a number of turns to match the impedance required by the circuit. The ferrite bar is able to focus signals to itself which in turn induces a current in the coil. While impedance is an important issue, simple dipole antennas can be sized by the 468/Frequency in mHz formula. It will give the the length of an antenna in feet. You divide the outcome by 2 to find out what each side length should be. The impedance of an antenna can ofter be adjusted by its shape. The 90 degree V shape yields a near perfect 50 ohms impedance which is commonly used for transmitters and transceivers where as the flat top diode has a higher impedance. The ARRL has good books on antennas. You might want to go to the library and look at a few of them.
What is the formula to calculate length of the wire?
There is no formula to calculate the length of a wire. The length of a wire is determined by the distance from the power source to where the load is situated.
Does the metal need to be an certain size or length for an electromagnet?
You can make any metal piece of any size an electromagnet by wounding a conducting wire around it and passing an electric current through it....
How does the resistance of a wire vary with its length?
resistance of wire increases with increases of length
What is the metal used in wire?
In most cases, copper is the metal used in wire.
What is thicker 28 or 30 gauge?
The thickness of metal wire is inversely proportional to the guage number of the metal wire. So 28 guage metal wire is thicker than 30 guage metal wire.
What is the best gauge copper wire to use for a radio antenna?
use a stronger wire for longer antennas...the gauge may not be as important as the strength if you string it outside.
What does grounded out mean in wiring of automobile?
On an automobile there is no (negative wire), the entire metal frame of the automobile is basically the negative wire. Grounded out means that a positive wire in the system has had the plastic covering somehow torn off and the bare wire is touching a part of the metal on the vehicle or a sharp piece of the vehicles metal has cut into a positive cable, either way it has "grounded out" (Bad thing), not to be confused with just plain "grounded" which is a good thing.
