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If an incandescent lamp is operated on a low-frequency current, the filament cools on each half-cycle of the alternating current, leading to perceptible change in brightness and flicker of the lamps ; the effect is more pronounced with arc lamps, and the later mercury-vapor and fluorescent lamps.
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If and incandescent
If the appliance is one whose purpose is for light or heat ( such as an incandescent lightbulb or electric oven ) then the lighting or heating elements may be considered as a type of fire ; if so, then turning them on constitutes both " lighting a fire " ( category 37 ) and " cooking " ( a form of baking, category 11 ), and turning them off would be " extinguishing a fire " ( category 36 ).
If and lamp
If flammable gas mixtures were present, the flame of the Davy lamp burned higher with a blue tinge.
If the church does not have a sanctuary lamp the centermost lamp on the seven-branch may remain lit as an eternal flame.
If there occurs an emergency at night it may take some time to make a light to light a lamp.
If the bottom lamp and some lamps on the top row are lit, this means permission to go in a direction shown.
If the only work to be done is maintenance ( i. e. changing a lamp or burnt out gel ) then the Production or Master Electrician will be in charge and will direct the Electrics crew.
If this type of lamp is broken it can easily start a fire.
If the wick is too high, and extends beyond the burner cone at the top of the wick tube, the lamp will produce smoke and soot ( unburned carbon ).
If the threshold element is a neon lamp, the circuit also provides a flash of light with each discharge of the capacitor.
If a BGA is found to be badly soldered, it can be removed in a rework station, which is a jig fitted with infrared lamp ( or hot air ), a thermocouple and a vacuum device for lifting the package.
If keratoconus is suspected, the ophthalmologist or optometrist will search for other characteristic findings of the disease by means of slit lamp examination of the cornea.
If both sensors show the same output or the rear O < sub > 2 </ sub > is " switching ", the computer recognizes that the catalytic converter either is not functioning or has been removed, and will operate a malfunction indicator lamp and affect engine performance.
If one lamp fails during a presentation, the presenter can merely move a lever to slide the spare into position and continue with the presentation, without needing to open the projection unit or waiting for the failed bulb to cool before replacing it.
If external triggering is used, the spark streamers may still be in contact with the glass when the full current load passes through the tube, causing wall ablation, or in extreme cases, cracking or even explosion of the lamp.
If a naked flame was thus enclosed totally by such a gauze, then methane could pass into the lamp and burn safely above the flame.
If the lamp failed ( an open circuit ), the current through the string became zero, causing the voltage of the circuit ( thousands of volts ) to be imposed across the insulating film, penetrating it ( see Ohm's law ).
If a tinfoil hat is placed on the globe, capacitive coupling can transfer enough current through the foil to give a small arc burn or light a small lamp connected to earth ground.
If the initial polarization filter is inserted between the lamp and the image generation element, the light intensity striking the image element is not any higher than normal without the polarizing filter, and overall image contrast transmitted to the screen is not affected.
If they use a starting electrode, there is always a thermal shorting switch to eliminate any electrical potential between the main electrode and the starting electrode once the lamp is lit.
If the discharge should be interrupted ( e. g. by interruption of the electric supply ), it is not possible for the lamp to restrike until the bulb cools enough for the pressure to fall considerably.
If the current through the lamp increases, the inductor reduces the voltage to keep the current limited.
If power is interrupted, even briefly, the lamp's arc will extinguish, and the high pressure that exists in the hot arc tube will prevent restriking the arc ; with a normal ignitor a cool-down period of 5 – 10 minutes will be required before the lamp can be restarted, but with special ignitors with specially designed lamps, the arc can be immediately re-established.
If a lamp is dropped, or ruptures while in service, pieces of the lamp envelope can be thrown at high speed.
If and is
If the circumstances are faced frankly it is not reasonable to expect this to be true.
If his dancers are sometimes made to look as if they might be creatures from Mars, this is consistent with his intention of placing them in the orbit of another world, a world in which they are freed of their pedestrian identities.
If a work is divided into several large segments, a last-minute drawing of random numbers may determine the order of the segments for any particular performance.
If they avoid the use of the pungent, outlawed four-letter word it is because it is taboo ; ;
If Wilhelm Reich is the Moses who has led them out of the Egypt of sexual slavery, Dylan Thomas is the poet who offers them the Dionysian dialectic of justification for their indulgence in liquor, marijuana, sex, and jazz.
If he is the child of nothingness, if he is the predestined victim of an age of atomic wars, then he will consult only his own organic needs and go beyond good and evil.
If it is an honest feeling, then why should she not yield to it??
If he thus achieves a lyrical, dreamlike, drugged intensity, he pays the price for his indulgence by producing work -- Allen Ginsberg's `` Howl '' is a striking example of this tendency -- that is disoriented, Dionysian but without depth and without Apollonian control.
If love reflects the nature of man, as Ortega Y Gasset believes, if the person in love betrays decisively what he is by his behavior in love, then the writers of the beat generation are creating a new literary genre.
If he is good, he may not be legal ; ;
If the man on the sidewalk is surprised at this question, it has served as an exclamation.
If the existent form is to be retained new factors that reinforce it must be introduced into the situation.
If we remove ourselves for a moment from our time and our infatuation with mental disease, isn't there something absurd about a hero in a novel who is defeated by his infantile neurosis??
If many of the characters in contemporary novels appear to be the bloodless relations of characters in a case history it is because the novelist is often forgetful today that those things that we call character manifest themselves in surface behavior, that the ego is still the executive agency of personality, and that all we know of personality must be discerned through the ego.
If he is a traditionalist, he is an eclectic traditionalist.
If our sincerity is granted, and it is granted, the discrepancy can only be explained by the fact that we have come to believe hearsay and legend about ourselves in preference to an understanding gained by earnest self-examination.
If to be innocent is to be helpless, then I had been -- as are we all -- helpless at the start.
If and operated
If the trip mechanism is operated when the clutch would otherwise disengage the clutch remains engaged.
If a particular KR is inadequate in some way, that set of problematic KR elements may be transformed by importing them into a KBS, modified and operated on to eliminate the problematic elements or augmented with additional knowledge imported from other sources, and then exported into a different, more appropriate KR.
If rotary pumps are operated at high speeds, the fluids will cause erosion, eventually developing enlarged clearances through which liquid can pass, reducing the efficiency of the pump.
If the engine must be operated in any orientation ( for example a chain saw ), a float chamber cannot work.
If the delegation of a power to the federal government operated as a denial (" prohibit ") of that power to the respective States, then every power " delegated to the United States government by the Constitution " would also be a power " prohibited by it to the States respectively ", such that the set of powers denied to the several States would entirely encompass the set of powers delegated to the federal government.
If operated from a simple power supply without current limiting, this reduction in resistance would lead to damage to the power supply and overheating of the tube electrodes.
If the cells are designed for no stirring, they can be operated with static pools of molten aluminium so that the impurities either rise to the top of the metallic aluminium, or else sink to the bottom, leaving high-purity aluminium in the middle.
If each switch is operated by a key on a typewriter, and the bulbs are labelled with letters, then such a system can be used for encryption by choosing the wiring between the keys and the bulb: for example, typing the letter < tt > A </ tt > would make the bulb labelled < tt > Q </ tt > light up.
If very high gain is needed ( 10 < sup > 5 </ sup > to 10 < sup > 6 </ sup >), certain APDs ( single-photon avalanche diodes ) can be operated with a reverse voltage above the APD's breakdown voltage.
If the SIR were considered part of the subway, this would be the oldest continually operated subway system right-of-way in New York City.
If Gauge Change Trains are operated, the time will be cut to 1 hour 19 minutes, and if the entire route is converted to Shinkansen track, travel time will be just 41 minutes.
If it is not operated frequently enough, the lubricant on the seals slowly evaporates, and then the seals begin to leak until the system is no longer functional and must be recharged.
If the chain is not being used for a high wear application ( for instance if it is just transmitting motion from a hand operated lever to a control shaft on a machine, or a sliding door on an oven ), then one of the simpler types of chain may still be used.
If a U. S. vehicle was equipped with overdrive, it was very likely to be a Borg-Warner type, operated by briefly backing off the gas when above 28 mph to enable, and momentarily flooring the gas pedal to return to normal gear.
If the full power of reverse thrust is not desirable, thrust reverse can be operated with the throttles set at less than full power, even down to idle power, which reduces stress and wear on engine components.
If desired, the Type 412 or 418, with or without the Type 941, could be operated independently of the other machines.
If the traction current line shares the pylon with a three-phase alternating current line operated by more than 220kV, the isolation of the traction current line must be designed for 220kV.
If expresses on other sectors are included, there was a period in the early 1990s when British Rail operated more 100 mph services per day than any other country.
If an engine is only operated at low rpm for its early life ( e. g. in a gently driven automobile ) then abruptly used in the higher rpm range ( e. g. by a new owner ), the slight stretching of the connecting rods at high speed can enable the top compression ring to contact the wear ridge, breaking the ring.
If both channels operated at the same clock speed, the parallel channel would be eight times faster.
If the lever is free to move based on the locking bed, contacts on the levers actuate the switches and signals which are operated electrically or electro-pneumatically.
If a high-pressure diesel fuel injector is removed from its seat and operated in open air, there is a risk to the operator of injury by hypodermic jet-injection, even with only 100 psi pressure.
If a firm operated internally under the market system, many contracts would be required ( for instance, even for procuring a pen or delivering a presentation ).
The Department of Buildings and Construction's preliminary report stated " If this was a privately operated structure, this office would have no alternative other than to give the operator 30 to 60 days to rewire the structure.
3.373 seconds.