sir ..i wanna know dt if.. charges(electrons) are not accelerated in a conductor(appliance..like bulb)..when a dc voltage is apllied across its ends then why is dat a bulb or LED generates electromagnetic radiations.(light)...vdout accelerating the charges ??????
10 years ago
by
overdozed
Ans
1
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In LEDs and bulbs the electromagnetic radiations are produced from the jumping of electrons from a higher energy level to a lower energy level i.e. from conduction to valence band.
10 years ago
by
Bhavya Popli
Ans
2
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in bulb joules law of heating is applied by which filament(tungsten resistivity=52.3 ohm m)gets heated up and simultaneously electrons get excited.when they fall back from higher energy level to lower energy level difference in energy is emitted as light.ACCORDING TO WWEIN'S DISPLACEMENT LAW WAVELENGTH INVERSELY PROPORTIONAL TO ABSOLUTE TEMPERATURE.AS WAVELENGTH INCREASES IT MOVES FROM INFRARED REGION TO VISIBLE REGION.
9 years ago
by
REEMA S