To save power, light emitting diodes (LEDs) are usually switched on and off several times per second, relying upon persistence of vision to make them appear continuously lit. If an LED is switched off half the time, only half as much current will flow through it during a given time compared to the current that would have flowed had the LED been on the entire time. Since the equations for power dissipated through a resistance state that P = IV and P = 1²R, how much power is used by the LED when cycling on and off for equal time intervals, compared to what would have been used if it remained on continuously? You may assume the resistance of the LED and the applied voltage remain constant. O It uses 1/16 the power of a continuously lit LED. O It uses 1/4 the power of a continuously lit LED. It uses twice the power of a continuously lit LED. It uses 1/2 the power of a continuously lit LED.

To save power, light emitting diodes (LEDs) are usually switched on and off several times per second, relying upon persistence of vision to make them appear continuously lit. If an LED is switched off half the time, only half as much current will flow through it during a given time compared to the current that would have flowed had the LED been on the entire time. Since the equations for power dissipated through a resistance state that P = IV and P = 1²R, how much power is used by the LED when cycling on and off for equal time intervals, compared to what would have been used if it remained on continuously? You may assume the resistance of the LED and the applied voltage remain constant. O It uses 1/16 the power of a continuously lit LED. O It uses 1/4 the power of a continuously lit LED. It uses twice the power of a continuously lit LED. It uses 1/2 the power of a continuously lit LED.

College Physics

11th Edition

ISBN:9781305952300

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter1: Units, Trigonometry. And Vectors

Section: Chapter Questions

Problem 1CQ: Estimate the order of magnitude of the length, in meters, of each of the following; (a) a mouse, (b)...

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