Atest tube is in uniform circular motion in a centrifuge, which is a piece of scientific equipment used to separate solids from liquids by spinning its contents very quickly. the velocity of the test tube a. does not change. b. is constantly changing. c. depends on the mass of the centrifuge. d. is perpendicular to the direction of motion.
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The lid of a pressure cooker forms a nearly airtight seal. steam builds up pressure and increases temperature within the pressure cooker so that food cooks faster than it does in an ordinary pot. the system is defined as the pressure cooker and the water and steam within it. if 2.0 g of water is sealed in a pressure cooker and then vaporized by heating, and 5655 j must be added as heat to completely vaporize the water, what is the change in the system’s internal energy? answer in units of j.