Concept explainers
Shake Flashlight A shake flashlight uses the mechanical energy 0f the shaking action to charge a capacitor that operates the LED light. (a) If you shake the flashlight with an average force of 2.0 N at a speed of 0.85 m/s, what mechanical power do you produce? (b) If you shake the flashlight for 30 seconds, and 75% of the mechanical energy is converted to electrical energy, how much energy is stored in the capacitor? (c) If the LED lamp draws 0.032 A at 3.1 V, for how much time will the capacitor operate the LED?
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