why?
2006-12-25 15:58:30 · 10 answers · asked by chinna u 1 in Science & Mathematics ➔ Physics
On most TV's the tube takes some time to become bright as the power supply builds up to operating level. The delay is much less with the sound system because the voltages are lower and LCD screens come up very quickly. Most TV's with tubes are now "instant on" which means they are supplied with electricity when "off" so they are preheated. Before "instant on", tube type TV's took close to 2 minutes to show an image.
2006-12-25 16:17:45 · answer #1 · answered by Mike1942f 7 · 1⤊ 0⤋
when we switch on the tv, the sound is transmitted immediately, but light could be produced only after the filament in the picture tube gets heated up to the necessary temperature. hence, when we switch on the tv, we observe sound first and then light.
2006-12-26 00:22:34 · answer #2 · answered by silambs 2 · 0⤊ 0⤋
Not with all TVs. This varies from barand from brand and depends on the picture tube. Go to a TV shop and compare different brands. I had observed that Sony takes the logest time. SOme TVs gives pictures almost instantly. It is because of the time the picture tube take to warm up.
2006-12-26 00:11:03 · answer #3 · answered by rups 3 · 1⤊ 0⤋
If your TV has a CRT, it takes a few seconds for the filament in the electron gun located in the neck of the tube to reach operating temperature. At that point it will begin emitting the electron beam that "draws" the picture on the screen.
2006-12-26 00:33:24 · answer #4 · answered by charley128 5 · 0⤊ 0⤋
Even im wonderin as light is faster than sound!!!!
But here its the opposite!!
2006-12-26 00:10:57 · answer #5 · answered by grass_hopper_king 2 · 0⤊ 0⤋
Because light is faster than sound.
2006-12-26 00:00:22 · answer #6 · answered by Anonymous · 0⤊ 2⤋
cause the picture takes a second to come on. sound is instant. who cares?
2006-12-25 23:59:52 · answer #7 · answered by Steve V 3 · 0⤊ 1⤋
Monitors need to be wane up
2006-12-26 00:11:25 · answer #8 · answered by JAMES 4 · 0⤊ 0⤋
simply!! bcos speed of light is more than sound
2006-12-26 02:05:37 · answer #9 · answered by pratish 1 · 0⤊ 1⤋
wrong observation
2006-12-26 12:39:10 · answer #10 · answered by ram kumar 2 · 0⤊ 0⤋