[permalink] [id link]
If the coil of wire is wrapped around a material with no special magnetic properties ( e. g., cardboard ), it will tend to generate a very weak field.
from
Wikipedia
Some Related Sentences
If and coil
* Nonlinearity: If the current through a ferromagnetic core coil is high enough that the magnetic core saturates, the inductance will not remain constant but will change with the current through the device.
If the coil is designed to be energized with alternating current ( AC ), a small copper " shading ring " can be crimped to the end of the solenoid, creating a small out-of-phase current which increases the minimum pull on the armature during the AC cycle.
If the overload senses excess current in the load, the coil is de-energized.
If the turns of the coil are oriented perpendicularly to the magnetic field lines, the flux is the product of the magnetic flux density B and the area A through which it cuts.
If the secondary coil is attached to a load that allows current to flow, electrical power is transmitted from the primary circuit to the secondary circuit.
If the bottom coil ( as shown ) leads in phase, then the motor will move downward ( in the drawing ), and vice versa.
If a path can be traced between the left side of the rung and the output, through asserted ( true or " closed ") contacts, the rung is true and the output coil storage bit is asserted ( 1 ) or true.
If no path can be traced, then the output is false ( 0 ) and the " coil " by analogy to electro-mechanical relays is considered " de-energized ".
If the fingers of the right hand are curled around the coil in the direction of current flow ( conventional current, flow of positive charge ) through the windings, the thumb points in the direction of the field inside the coil.
If a piece of electrically conductive metal is close to the coil, eddy currents will be induced in the metal, and this produces an alternating electric field of its own.
If another coil is used to measure the electric field ( acting as a magnetometer ), the change in the magnetic field due to the metallic object can be detected.
If the terminals of a coil are connected, the shaft becomes harder to turn.
If too much power is applied to the voice coil as compared to its ability to shed heat, it will eventually exceed a maximum safe temperature.
If interference was encountered, the smaller coil would be slid further out of the larger, loosening the coupling and narrowing the bandwidth, to reject the interfering signal.
If the polarity of one coil is reversed so that M is negative, then the parallel inductance is nearly zero or the combination is almost non-inductive.
If a coil is made using coaxial cable near to the feed point of a balanced antenna, then the RF current that flows on the outer surface of the coaxial cable can be attenuated.
If the magnetic field in the plasma is not stationary, either because the plasma as a whole is transient or because the fields are periodic ( radio-frequency heating ), the rate of change of the magnetic field with time (, read " B-dot ") can be measured locally with a loop or coil of wire.
If it was an adequate meal, the snake will find a warm, safe location in which to coil up and rest until the prey is digested.
If the plate receives a mixture of positive and negative charges as, for example, from an induction coil, a mixed figure results, consisting of a large red central nucleus, corresponding to the negative charge, surrounded by yellow rays, corresponding to the positive charge.
If sufficient voltage appears across the ELCB's sense coil, it will switch off the power, and remain off until manually reset.
If disturbed, a gartersnake may coil and strike, but typically it will hide its head and flail its tail.
If that load has low resistance, the current will be larger and the voice coil will be more strongly forced to decelerate.
If too much deformation occurs, the adjacent turns of the coil touch one another, causing an electrical short and local overheating, which quickly leads to failure of the filament.
If and wire
If he backed against the fence, one of the cars would brush him as it passed, and he would be cruelly lacerated by the wire.
If for instance there had been a wire walker the reprise would involve two chairs with a piece of rope between and the clown trying to imitate the artiste by trying to walk between them with the resulting falls and cascades bringing laughter from the audience.
If the weight of the roadway per unit length is w and the weight of the cable and the wire supporting the bridge is negligible in comparison, then the weight on the cable from c to r is wx where x is the horizontal distance between c to r. Proceeding as before gives the differential equation
If not, actors frequently train in preparation for their roles, or the action director may rely more on stylized action or filmmaking tricks like camera angles, editing, doubles, undercranking, wire work, and computer-generated imagery.
If the gas pressure is reduced, the cooling effect will decrease, hence the equilibrium temperature of the wire will increase.
If this disc was removed from the machine and put on a similar machine provided with a contact point, the embossed record would cause the signals to be repeated into another wire.
So If a third metal is inserted in either wire and if the two new junctions are at the same temperature, there will be no net voltage generated by the new metal.
If the signal were normally open, no wire failure would be detected.
If pyramid scheme chain letters are sent through email it may constitute wire fraud.
If a micrometeorite of about 10 µm impacted, it would fracture the wire, destroy the electrical connection, and thus record the event.
If corrosion occurs, it occurs on the outside of the wire, not on the gas-tight contact where oxygen cannot penetrate to form oxides.
If the wire had negligible mass, the center of oscillation was close to the center of gravity of the sphere.
" If an attacker can modify the message on the wire, and can guess the format of the unencrypted message, the attacker could be able to change the amount of the transaction, or the recipient of the funds, e. g. "< tt > TRANSFER $ 0100000. 00 TO ACCOUNT # 227 </ tt >.
If the area available for the windings is filled up, more turns require going to a smaller diameter of wire, which has higher resistance, which cancels the advantage of using more turns.
If the position and current of the wire are reflected across the dotted line, the magnetic field it generates would not be reflected: Instead, it would be reflected and reversed.
If a wire breaks or tension is otherwise lost, the pulley falls back toward the mast, and one of its teeth will jam against the stop.
If we wrap our right hand around a wire with the thumb pointing in the direction of the current, the curl of the fingers shows how the field behaves.
If he had missed the boxes, no safety wire or parachute would have stopped him falling to the bottom of the ravine.
If copper wire is used, nitrogen must be used as a cover gas to prevent the copper oxides from forming during the wire bonding process.
If a wire joins the battery to one bulb, to the next bulb, to the next bulb, to the next bulb, then back to the battery, in one continuous loop, the bulbs are said to be in series.
If more than one team owner claims a player, a team's waiver wire position determines who gets the player.
If the inner wire is solid, as in automotive and lawnmower throttle and choke applications, it may simply have a bend at one or both ends to engage what ever it pushes or pulls.
If the separation D is much greater than the wire diameter d then this is approximately
1.009 seconds.