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Review Example: FrictionAssuming that Superman weighs 200 lb, the boat weighs 10 tons, and the coefficients of friction between the boat and dock are s = 0.5 and k = 0.25 find:The minimum coefficient of static friction between Supermans feet and the dock to move the boat at all.The minimum coefficient of static friction to accelerate the boat at 10 ft/s2.

Supermans Sticky FeetExample: Snakes on a PlaneIs friction good or bad? How does it affect you in your daily life?Snakes are masters at manipulating friction to moveThey (and you) cant move without frictionThey also cant move without different friction coefficients in different directions!Snakes manipulate friction using their scales