WEBVTT
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This is College Physics
Answers with Shaun Dychko.
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Begin by writing down the
information we're given.
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We're told that the resistance in this
DVD indicator light is 140 ohms
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and the current going
through it is 25 milliamps
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which we convert into amps by
multiplying by ten to the minus three
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because that's what the prefix milli means.
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So the voltage will be the current
multiplied by resistance
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so 25 times ten to minus three
amps multiplied by 149 ohms,
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gives three and a half volts.