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## Bell-Ringers

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**Bell-Ringers**16 June 2009**The Prediction**• “Give me a place to stand and a lever long enough and I will move the earth.” • Do you think this is possible? Why or why not?**Astronomers know the earth's mass. On earth a body**possessing such a mass would weigh in round numbers 6,000,000,000,000,000,000,000 tons**Supposing a man could lift only 60 kg directly, to "lift the**earth" he would need a lever with a long arm that would be longer than the shorter arm by 1,000,000,000,000,000,000,000 times!!**You can easily figure it out that to have the end of the**short arm rise by one centimeter; the other end must describe through space the huge arc of 1,000,000,000,000,000,000 km**Presuming Archimedes could have lifted 60 Kg one meter in**one second- the work of almost one horsepower! - to lift the earth by just one centimeter, even then he would need 1,000,000,000,000,000,000,000 seconds (30 million million years).**Even if Archimedes had been able to push the lever with a**speed of 0.34 km/sec the speed of sound, he would have lifted the earth by one centimeter only after 93,264,094,069,895.84265 years**If he had pushed the lever with the speed of light, 300,000**km/sec, natures fastest possible- he would have lifted the earth by one centimeter only after ten million years of pushing.**Bell-Ringer**• 17 June 2009 • Learning Target: Explain how inclined planes make work easier. • Name one inclined plane that you used today.**Bell-Ringer**17 June 2009 Learning Target: Identify properties of polymers and metals. What is a “polymer”? What is a metal?