Electronic Salvage SMD resistor from CFL to LED Flashlight powered by rechargeable lithium battery

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Description: I salvaged SMD resistors from broken CFL nightlight to make LED flashlight. Since it has 150 ohm SMD resistor, I can solder together a small portable flashlight powered by rechargeable 250 mAh lithium battery.

How long does light take to travel around the earth- Math and Science Word Problem Episode 1

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Description: Today's practical Math question: How long does light take to travel around the earth? You will need to know the circumference of the earth and the speed of light to solve this question.