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Inverse Squared Law Quiz

  1. A light bulb looks dimmer the further away it is because

  2. Walking into your basement one night, you notice you can see only 10 feet with your trusty 50 Watt flashlight. How strong must your flashlight be in order to see the full 20 feet of your basement?

  3. While waiting for your bus you see in the distance the familiar glare of its headlights. With your handy light meter you measure the intensity of its light as 10 lumen. After 10 seconds you measure the intensity at 20 lumen. What can you infer about the bus during that 10 second interval?